研究者データベース

三澤 弘明(ミサワ ヒロアキ)
電子科学研究所 附属グリーンナノテクノロジー研究センター
特任教授

基本情報

所属

  • 電子科学研究所 附属グリーンナノテクノロジー研究センター

職名

  • 特任教授

学位

  • 理学博士(1984年 筑波大学)

ホームページURL

J-Global ID

研究キーワード

  • 光化学   プラズモンの化学   

研究分野

  • ナノテク・材料 / 応用物理一般
  • ナノテク・材料 / 基礎物理化学

職歴

  • 2020年04月 - 現在 北海道大学 電子科学研究所 特任教授
  • 2003年05月 - 2020年03月 北海道大学 電子科学研究所 教授
  • 2009年10月 - 2013年09月 北海道大学 電子科学研究所 所長
  • 2006年 - 2009年 北海道大学 電子科学研究所附属ナノテクノロジー研究センター センター長
  • 1997年04月 - 2003年04月 徳島大学 大学院工学研究科 教授
  • 1995年11月 - 1997年03月 徳島大学 工学部 教授
  • 1993年04月 - 1995年10月 徳島大学 工学部 助教授
  • 1991年04月 - 1993年03月 新技術事業団 増原極微変換プロジェクト極微制御グループ グループリーダー
  • 1988年12月 - 1991年03月 新技術事業団 増原極微変換プロジェクト極微制御グループ 研究員
  • 1986年 - 1988年 筑波大学 化学系 助手
  • 1984年04月 - 1986年02月 米国テキサス大学ダラス校 博士研究員

学歴

  •         - 1984年   筑波大学大学院   化学研究科   化学専攻博士課程修了
  •         - 1984年   筑波大学
  •         - 1982年   筑波大学大学院   理工学研究科   理工学専攻修士課程修了
  •         - 1979年   東京都立大学   工学部   工業化学科 卒業
  •         - 1979年   東京都立大学

所属学協会

  • 光化学協会   アメリカ化学会 (American Chemical Society)   応用物理学会   高分子学会   日本化学会   

研究活動情報

論文

  • Tomoya Oshikiri, Haruki Jo, Xu Shi, Hiroaki Misawa
    Chemistry – A European Journal 28 24 e202200288  2022年02月20日 [査読有り]
  • Giles Allison, Amrita Kumar Sana, Yuta Ogawa, Hidemi Kato, Kosei Ueno, Hiroaki Misawa, Koki Hayashi, Hironori Suzuki
    Nature Communications 2021年12月 [査読有り]
  • Palyam Subramanyam, Bhagatram Meena, Vasudevanpillai Biju, Hiroaki Misawa, Subrahmanyam Challapalli
    Journal of Photochemistry and Photobiology C: Photochemistry Reviews 100472 - 100472 2021年11月
  • Tomoya Oshikiri, Quan Sun, Hiroki Yamada, Shuai Zu, Keiji Sasaki, Hiroaki Misawa
    ACS Nano 15 10 16802 - 16810 2021年09月28日
  • Xiaoqian Zang, Xu Shi, Tomoya Oshikiri, Kosei Ueno, Yuji Sunaba, Keiji Sasaki, Hiroaki Misawa
    The Journal of Physical Chemistry C 125 36 19880 - 19886 2021年09月16日
  • Yoshiki Suganami, Tomoya Oshikiri, Xu Shi, Hiroaki Misawa
    Angewandte Chemie International Edition 2021年07月21日
  • Shuai Zu, Quan Sun, En Cao, Tomoya Oshikiri, Hiroaki Misawa
    NANO LETTERS 21 11 4780 - 4786 2021年06月 
    The spatiotemporal origin of plasmonic chiroptical responses in nanostructures remains unexplored and unclear. Here, two orthogonally oriented Au nanorods as a prototype were investigated, with a giant chiroptical response caused by antisymmetric and symmetric mode excitations for obliquely incident left-handed circular polarization (LCP) and right-handed circular polarization (RCP) light. Time-resolved photoemission electron microscopy (PEEM) was employed to measure the near-field spatial distributions, spectra, and spatiotemporal dynamics of plasmonic modes associated with the chiroptical responses at the nanofemto scale, verifying the characteristic near-field distributions at the resonant wavelengths of the two modes and a very large spectral dichroism for LCP and RCP. More importantly, eigenmode excitations and their contributions to the ultrafast plasmonic chiroptical response in the space-time domain were directly revealed, promoting a full understanding of the ultrafast chiral origin in complex nanostructures. These findings open a way to design chiroptical nanophotonic devices for spatiotemporal control of chiral light-matter interactions.
  • Daniel E. Gomez, Xu Shi, Tomoya Oshikiri, Ann Roberts, Hiroaki Misawa
    NANO LETTERS 21 9 3864 - 3870 2021年05月 
    We experimentally demonstrate and theoretically study the formation of coherent plasmon-exciton states which exhibit absorption of >90% of the incident light (at resonance) and cancellation of absorption. These coherent states result from the interaction between a material supporting an electronic excitation and a plasmonic structure capable of (near) perfect absorption of light. We illustrate the potential implications of these coherent states by measuring the charge separation attainable after photoexcitation. Our study opens the prospect for realizing devices that exploit coherent effects in applications.
  • Keisuke Nakamura, Tomoya Oshikiri, Kosei Ueno, Hiromichi Ohta, Hiroaki Misawa
    Chemistry Letters 50 2 374 - 377 2021年02月05日 [査読有り][通常論文]
  • Yanfeng Cao, Xu Shi, Tomoya Oshikiri, Shuai Zu, Yuji Sunaba, Keiji Sasaki, Hiroaki Misawa
    Chemical Communications 57 4 524 - 527 2021年01月14日 [査読有り][通常論文]
     

    The near field was tailored to be enhanced at the three-phase boundary of Au-NPs/TiO2/H2O for efficient water oxidation.

  • Palyam Subramanyam, Melepurath Deepa, Sai Santosh Kumar Raavi, Hiroaki Misawa, Vasudevanpillai Biju, Challapalli Subrahmanyam
    Nanoscale Advances 2 12 5591 - 5599 2020年12月01日 [査読有り][通常論文]
     

    A wide range of technologies has been developed for producing hydrogen economically and in greener ways.

  • Yaguang Wang, Xu Shi, Tomoya Oshikiri, Shuai Zu, Kosei Ueno, Hiroaki Misawa
    Nanoscale 12 44 22674 - 22679 2020年11月28日 [査読有り][通常論文]
     

    The plasmonic Ga2O3 photoanode with the interfacial TiO2 modification provide both a high reduction ability and an oxidation ability.

  • Kai Chen, Thang Duy Dao, Thien Duc Ngo, Hai Dang Ngo, Akemi Tamanai, Satoshi Ishii, Xiangping Li, Hiroaki Misawa, Tadaaki Nagao
    Nano Energy 76 104965 - 104965 2020年10月 [査読有り][通常論文]
  • Quan Sun, Shuai Zu, Hiroaki Misawa
    The Journal of Chemical Physics 153 12 120902 - 120902 2020年09月28日 [査読有り][通常論文]
     
    The near-field properties and dynamics of plasmonic nanostructures play a crucial role in several fundamental concepts in physics and chemistry, and they are widely relevant in plasmonic applications. Ultrafast photoemission electron microscopy (PEEM) is a novel approach that has been widely applied to probe plasmonic nanostructures from multiple domains. Furthermore, PEEM is the only technique that provides nanometer spatial resolution, sub-femtosecond temporal resolution, and tens to hundreds of millielectron volt energy resolution. This allows for extremely sensitive observations of plasmonic field oscillations, field dephasing, and hot electrons. This Perspective provides a brief overview of the basic principles and main applications of ultrafast PEEM. The research progress of ultrafast PEEM in plasmonics is highlighted from three points of view: near-field imaging, near-field spectroscopy, and ultrafast dynamics. Future applications of PEEM in plasmonics for the probing of plasmonic hot electron dynamics in the energy and time domains are proposed and discussed.
  • Xu Shi, Xiaowei Li, Takahiro Toda, Tomoya Oshikiri, Kosei Ueno, Kentaro Suzuki, Kei Murakoshi, Hiroaki Misawa
    ACS Applied Energy Materials 3 6 5675 - 5683 2020年06月22日 [査読有り][通常論文]
     
    Plasmon-induced carrier transfer at metallic nanoparticle/semiconductor heterojunctions has received great attention because of its tremendous potential in applications, such as photocatalysis and photoelectric and energy conversion. The interfacial structure of the heterojunction is known to play an important role in charge transfer as well as the subsequent chemical reactions. Here, we studied the Au nanoparticle (Au-NP)-loaded (100)-, (110)-, and (111)-oriented single-crystalline strontium titanate (STO) as a model to investigate the effects of interfacial structure on the plasmon-induced charge separation between the metallic nanoparticles and semiconductors. Via photoelectrochemical characterizations, we found that the efficiency of the plasmon-induced water oxidation reaction on STO(100) is more than 1.4 times higher than that on the other two orientation facets. This enhancement was demonstrated to stem from the high oxidation ability of plasmon-induced holes captured in the surface states. Furthermore, the molecular processes of water oxidation were investigated by monitoring the surface oxidation status of Au-NP/STO as intermediates of plasmon-induced water oxidation using in situ electrochemical surface-enhanced Raman spectroscopy. The onset potential of Au-O vibrations on Au-NP/STO(100) was determined to be 0.4 V more negative than that of Au-NP/STO(110), further confirming the higher oxidation ability of the plasmon-induced holes. Our observation provides an opportunity to efficiently modulate plasmon-excited hot-carrier reaction processes for photochemical applications through interfacial engineering.
  • Megumi Okazaki, Yoshiki Suganami, Naoki Hirayama, Hiroko Nakata, Tomoya Oshikiri, Toshiyuki Yokoi, Hiroaki Misawa, Kazuhiko Maeda
    ACS Applied Energy Materials 3 6 5142 - 5146 2020年06月22日 [査読有り][通常論文]
     
    Plasmonic Au/TiO2 thin film works as a stable water oxidation photoanode. Here we show that site-selective deposition of nanosized CoOx as a water oxidation cocatalyst at the edge of Au nanoparticles on the TiO2 film improves the photoelectrochemical water oxidation activity. The nanosized CoOx was deposited by a photoassisted electrochemical method onto the Au/TiO2 thin film. The CoOx loading amount was controllable by changing the amount of electric charge that flowed during the deposition, which influenced the photoelectrochemical performance. Under visible light, the optimized CoOx/Au/TiO2 thin film generated stable photoanodic current, which was similar to 3 times higher than that obtained using Au/TiO2.
  • Yaolong Li, Wei Liu, Yunkun Wang, Zhaohang Xue, Yu-Chen Leng, Aiqin Hu, Hong Yang, Ping-Heng Tan, Yunquan Liu, Hiroaki Misawa, Quan Sun, Yunan Gao, Xiaoyong Hu, Qihuang Gong
    Nano Letters 20 5 3747 - 3753 2020年05月13日 [査読有り][通常論文]
  • Tomoya Oshikiri, Xu Shi, Hiroaki Misawa
    European Journal of Inorganic Chemistry 2020 15-16 1396 - 1401 2020年04月30日 [査読有り][通常論文]
  • Yaolong Li, Quan Sun, Shuai Zu, Xu Shi, Yunquan Liu, Xiaoyong Hu, Kosei Ueno, Qihuang Gong, Hiroaki Misawa
    Physical Review Letters 124 16 163901 - 163901 2020年04月24日 [査読有り][通常論文]
     
    Near-field enhancement and dephasing time play critical roles in several applications of localized surface plasmon resonance. Here, using an example gold dimer system, we reveal the correlation between the near-field enhancement and dephasing time via time-resolved photoemission electron microscopy. Compared with isolated particles, dimers with small gap sizes show stronger near-field enhancement and shorter dephasing times. These results are well reproduced by numerical simulations and further explained by a coupled dipole approximation model. The roles of near- and far-field coupling and plasmon localization in balancing near-field enhancement and dephasing time are also unveiled.
  • Wan-Ping Guo, Wei-Yun Liang, Chang-Wei Cheng, Wei-Lin Wu, Yen-Ting Wang, Quan Sun, Shuai Zu, Hiroaki Misawa, Pi-Ju Cheng, Shu-Wei Chang, Hyeyoung Ahn, Minn-Tsong Lin, Shangjr Gwo
    Nano Letters 20 4 2857 - 2864 2020年04月08日 [査読有り][通常論文]
     
    Two-dimensional spiral plasmonic structures have emerged as a versatile approach to generate near-field vortex fields with tunable topological charges. We demonstrate here a far-field approach to observe the chiral second-harmonic generation (SHG) at designated visible wavelengths from a single plasmonic vortex metalens. This metalens comprises an Archimedean spiral slit fabricated on atomically flat aluminum epitaxial film, which allows for precise tuning of plasmonic resonances and subsequent transfer of two-dimensional materials on top of the spiral slit. The nonlinear optical measurements show a giant SHG circular dichroism. Furthermore, we have achieved an enhanced chiral SHG conversion efficiency (about an order of magnitude greater than the bare aluminum lens) from monolayer tungsten disulfide (WS2)/aluminum metalens, which is designed at the C-exciton resonance of WS2. Since the C-exciton is not a valley exciton, the enhanced chiral SHG in this hybrid system originates from the plasmonic vortex field-enhanced SHG under the optical spin-orbit interaction.
  • Xiao-Yan Zhang, Zhe-Yu Li, Kose Ueno, Hiroaki Misawa, Nan-Qi Ren, Kai Sun
    Micromachines 11 2 207 - 207 2020年02月17日 [査読有り][通常論文]
     
    Minimum inhibition concentration (MIC) of antibiotic is an effective value to ascertain the agent and minimum dosage of inhibiting bacterial growth. However, current techniques to determine MIC are labor intensive and time-consuming, and require skilled operator and high initial concentration of bacteria. To simplify the operation and reduce the time of inhibition test, we developed a microfluidic system, containing a concentration generator and sub-micro-liter chambers, for rapid bacterial growth and inhibition test. To improve the mixing effect, a micropillar array in honeycomb-structure channels is designed, so the steady concentration gradient of amoxicillin can be generated. The flanged chambers are used to culture bacteria under the condition of continuous flow and the medium of chambers is refreshed constantly, which could supply the sufficient nutrient for bacteria growth and take away the metabolite. Based on the microfluidic platform, the bacterial growth with antibiotic inhibition on chip can be quantitatively measured and MIC can be obtained within six hours using low initial concentration of bacteria. Overall, this microfluidic platform has the potential to provide rapidness and effectiveness to screen bacteria and determine MIC of corresponding antibiotics in clinical therapies.
  • Mochamad Januar, Bei Liu, Jui-Ching Cheng, Koji Hatanaka, Hiroaki Misawa, Hui-Hsin Hsiao, Kou-Chen Liu
    The Journal of Physical Chemistry C 124 5 3250 - 3259 2020年02月06日 [査読有り][通常論文]
  • Tomoya Oshikiri, Hiroki Sawayanagi, Keisuke Nakamura, Kosei Ueno, Takayoshi Katase, Hiromichi Ohta, Hiroaki Misawa
    The Journal of Chemical Physics 152 3 034705 - 034705 2020年01月21日 [査読有り][通常論文]
  • Jinghuan Yang, Quan Sun, Wei Liu, Zhibin Zhang, Xiaoyong Hu, Kaihui Liu, Hong Yang, Hiroaki Misawa, Qihuang Gong
    Advanced Optical Materials 7 19 1900580 - 1900580 2019年10月 [査読有り][通常論文]
  • Kuang-Li Lee, Meng-Lin You, Xu Shi, Yi-Ru Li, Kosei Ueno, Hiroaki Misawa, Pei-Kuen Wei
    Applied Materials Today 16 72 - 82 2019年09月 [査読有り][通常論文]
  • Yanfeng Cao, Tomoya Oshikiri, Xu Shi, Kosei Ueno, Jie Li, Hiroaki Misawa
    ChemNanoMat 5 8 972 - 972 Wiley 2019年08月29日 [査読有り][通常論文]
  • Yanfeng Cao, Tomoya Oshikiri, Xu Shi, Kosei Ueno, Jie Li, Hiroaki Misawa
    ChemNanoMat 5 8 1008 - 1014 2019年08月 [査読有り][通常論文]
  • Tomoya Oshikiri, Kosei Ueno, Hiroaki Misawa
    Green Chemistry 21 16 4443 - 4448 2019年07月 [査読有り][通常論文]
     

    Ammonia photosynthesis under visible light irradiation via an associative pathway using a plasmonic photoanode and a zirconium cathode is proposed.

  • Quan Sun, Shuai Zu, Kosei Ueno, Qihuang Gong, Hiroaki Misawa
    Chin. J. Lasers 46 5 0508008 - 0508001 2019年05月 [査読有り][招待有り]
  • Wei‐Yi Tsai, Quan Sun, Guangwei Hu, Pin Chieh Wu, Ren Jie Lin, Cheng‐Wei Qiu, Kosei Ueno, Hiroaki Misawa, Din Ping Tsai
    Advanced Optical Materials 7 8 1801060 - 1801060 2019年04月21日 [査読有り][通常論文]
  • Miharu Eguchi, Jie Li, Kosei Ueno, Hiroaki Misawa
    Chemistry Letters 48 3 211 - 214 2019年03月05日 [査読有り][通常論文]
  • Quan Sun, Han Yu, Kosei Ueno, Shuai Zu, Yasutaka Matsuo, Hiroaki Misawa
    Opto-Electronic Advances 2 4 18003001 - 18003007 2019年03月 [査読有り][通常論文]
  • Kosei Ueno, Jinghuan Yang, Quan Sun, Daisuke Aoyo, Han Yu, Tomoya Oshikiri, Atsushi Kubo, Yasutaka Matsuo, Qihuang Gong, Hiroaki Misawa
    Applied Materials Today 14 159 - 165 2019年03月 [査読有り][通常論文]
     
    The construction of metallic nanostructures with strong near-field enhancement is becoming increasingly significant for the practical use of plasmonic devices, such as plasmonic sensors and light-energy conversion systems. Importantly, the near-field enhancement effect depends on the plasmon dephasing time. Here, we propose a method for controlling plasmon dephasing time by utilizing plasmonic coupling for stronger near-field enhancement. Ordered arrays of stacked nanogap gold (Au) structures composed of a metal/insulator/metal nanostructure were fabricated by electron beam lithography and dry etching processes on a niobium-doped titanium dioxide substrate. The dark plasmon mode was excited by the near-field coupling between the upper and lower Au nanostructures separated by an alumina layer with a thickness of 15 nm. A strong near-field enhancement effect was induced by the localization of the electromagnetic field between the upper and lower Au nanostructures and the longer plasmon dephasing time based on the excitation of the dark plasmon mode. It is noteworthy that the dephasing time of the dark plasmon mode measured by time-resolved photoemission electron microscopy was extended 3-fold compared with that of the plasmon mode of the Au nanoblock, which can be controlled by the structural design of the stacked nanogap Au structures. (C) 2018 Elsevier Ltd. All rights reserved.
  • Wei‐Yi Tsai, Tsung Lin Chung, Hui‐Hsin Hsiao, Jia‐Wern Chen, Ren Jie Lin, Pin Chieh Wu, Greg Sun, Chih‐Ming Wang, Hiroaki Misawa, Din Ping Tsai
    Advanced Materials 31 7 1806479 - 1806479 2019年02月 [査読有り][通常論文]
  • Hanfa Song, Quan Sun, Jie Li, Fan Yang, Jinghuan Yang, Yaolong Li, Kosei Ueno, Qihuang Gong, Hiroaki Misawa
    The Journal of Physical Chemistry C 123 2 1398 - 1405 2019年01月17日 [査読有り][通常論文]
  • Xiao-Yan Zhang, Zhe-Yu Li, Yu Zhang, Xiao-Qian Zang, Kosei Ueno, Hiroaki Misawa, Kai Sun
    Micromachines 10 1 55 - 55 2019年01月14日 [査読有り][通常論文]
     
    Capacitively coupled contactless conductivity detection (C4D) is an improved approach to avoid the problems of labor-intensive, time-consuming and insufficient accuracy of plate count as well as the high-cost apparatus of flow cytometry (FCM) in bacterial counting. This article describes a novel electrode-integrated printed-circuit-board (PCB)-based C4D device, which supports the simple and safe exchange of capillaries and improves the sensitivity and repeatability of the contactless detection. Furthermore, no syringe pump is needed in the detection, it reduces the system size, and, more importantly, avoids the effect on the bacteria due to high pressure. The recovered bacteria after C4D detection at excitation of 25 Vpp and 60–120 kHz were analyzed by flow cytometry, and a survival rate higher than 96% was given. It was verified that C4D detection did not influence the bacterial viability. Moreover, bacteria concentrations from 106 cells/mL to 108 cells/mL were measured in a linear range, and relative standard deviation (RSD) is below 0.2%. In addition, the effects on bacteria and C4D from background solutions were discussed. In contrast to common methods used in most laboratories, this method may provide a simple solution to in situ detection of bacterial cultures.
  • Weiwei Liu, Zijie Dai, Jing Yang, Quan Sun, Cheng Gong, Nan Zhang, Kosei Ueno, Hiroaki Misawa
    IEEE Photonics Technology Letters 30 24 2103 - 2106 2018年12月15日 [査読有り][通常論文]
  • Jinghuan Yang, Quan Sun, Kosei Ueno, Xu Shi, Tomoya Oshikiri, Hiroaki Misawa, Qihuang Gong
    Nature Communications 9 1 4858  2018年12月 [査読有り][通常論文]
  • Xu Shi, Kosei Ueno, Tomoya Oshikiri, Quan Sun, Keiji Sasaki, Hiroaki Misawa
    Nature Nanotechnology 13 10 953 - 958 2018年10月28日 [査読有り][通常論文]
  • Man-Nung Su, Quan Sun, Kosei Ueno, Wei-Shun Chang, Hiroaki Misawa, Stephan Link
    The Journal of Physical Chemistry C 122 31 18005 - 18011 2018年08月09日 [査読有り][通常論文]
  • Keisuke Nakamura, Tomoya Oshikiri, Kosei Ueno, Takayoshi Katase, Hiromichi Ohta, Hiroaki Misawa
    The Journal of Physical Chemistry C 122 25 14064 - 14071 2018年06月28日 [査読有り]
  • Kosei Ueno, Tomoya Oshikiri, Quan Sun, Xu Shi, Hiroaki Misawa
    Chemical Reviews 118 6 2955 - 2993 2018年03月28日 [査読有り][通常論文]
     
    Metallic nanoparticles such as silver and gold show localized surface plasmon resonances (LSPRs), which are associated with near-field enhancement effects in the vicinity of nanoparticles. Therefore, strong light-matter interaction is induced by the near-field enhancement effects of LSPRs. Because the resonant wavelength of LSPRs can be easily controlled by the size and shape of the metallic nanoparticles in the visible and near-infrared wavelength range, LSPRs have received considerable attention as optical antennae for light energy conversion systems such as solar cells. LSPRs decay very quickly as a result of light scattering and excitation of electron-hole pairs in the metal itself. However, in addition to the near-field enhancement effect, this light scattering and electron-hole pair excitation, which are known to cause loss of LSPRs, can be utilized as a solar cell enhancement mechanism. Here, we focus on plasmonic solid-state solar cells. The mechanisms of the light scattering by LSPRs, near-field enhancement, and plasmon-induced charge separation based on electron-hole pair excitations can be clarified. We review the related studies from the viewpoint of these mechanisms rather than material science.
  • Quan Sun, Kosei Ueno, Hiroaki Misawa
    The 9th International Symposium on Ultrafast Phenomena and Terahertz Waves OSA 2018年 [査読有り][通常論文]
  • Chung V. Hoang, Koki Hayashi, Yasuo Ito, Naoki Gorai, Giles Allison, Xu Shi, Quan Sun, Zhenzhou Cheng, Kosei Ueno, Keisuke Goda, Hiroaki Misawa
    NATURE COMMUNICATIONS 8 1 2017年10月 [査読有り][通常論文]
     
    Plasmon-induced hot-electron generation has recently received considerable interest and has been studied to develop novel applications in optoelectronics, photovoltaics and green chemistry. Such hot electrons are typically generated from either localized plasmons in metal nanoparticles or propagating plasmons in patterned metal nanostructures. Here we simultaneously generate these heterogeneous plasmon-induced hot electrons and exploit their cooperative interplay in a single metal-semiconductor device to demonstrate, as an example, wavelength-controlled polarity-switchable photoconductivity. Specifically, the dual-plasmon device produces a net photocurrent whose polarity is determined by the balance in population and directionality between the hot electrons from localized and propagating plasmons. The current responsivity and polarity-switching wavelength of the device can be varied over the entire visible spectrum by tailoring the hot-electron interplay in various ways. This phenomenon may provide flexibility to manipulate the electrical output from light-matter interaction and offer opportunities for biosensors, long-distance communications, and photoconversion applications.
  • Jingchun Guo, Kosei Ueno, Jinghuan Yang, Xu Shi, Jie Li, Quan Sun, Tomoya Oshikiri, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY C 121 39 21627 - 21633 2017年10月 [査読有り][通常論文]
     
    Near-field spectrum measurement techniques, including near-field scanning optical microscopy, electron energy loss spectroscopy, and multiphoton photoemission electron microscopy, are powerful means to investigate near-field interactions directly on closely spaced metallic nanoparticles or a metallic nanostructure coupled with optical modes, such as whispering gallery mode and waveguide mode, which are called coupled plasmonic systems. In the present study, we have successfully measured the near-field spectra of coupled plasmonic systems using a simple photoelectrochemical measurement based on plasmon-induced water oxidation. Coupling was explored between the localized surface plasmon resonance (LSPR.) mode and waveguide mode of periodic gold nanogratings patterned on a thin titanium dioxide waveguide film. It is known that the far-field reflection spectrum of this waveguide-LSPR coupling system shows a complicated shape with multiple peaks, and the coupling has been explored by numerical electromagnetic simulations so far. However, in this study, it was clearly elucidated that an internal quantum efficiency (IQE) spectrum observed in the plasmon-induced photocurrent generation has successfully reproduced the near-field spectrum predicted by electromagnetic simulations under the coupling conditions. The photocurrent generation based on the plasmon-induced charge separation is due to the near-field effect, and it can be considered that the IQE spectrum corresponds to the near-field spectrum. This study paves a new way to indirectly measure the near-field spectrum of plasmonic systems.
  • Jinghuan Yang, Quan Sun, Han Yu, Kosei Ueno, Hiroaki Misawa, Qihuang Gong
    PHOTONICS RESEARCH 5 3 187 - 193 2017年06月 [査読有り][通常論文]
     
    We investigate the superposition properties of the dipole and quadrupole plasmon modes in the near field both experimentally, by using photoemission electron microscopy (PEEM), and theoretically. In particular, the asymmetric near-field distributions on gold (Au) nanodisks and nanoblocks under oblique incidence with different polarizations are investigated in detail. The results of PEEM measurements show that the evolutions of the asymmetric near-field distributions are different between the excitation with s-polarized and p-polarized light. The experimental results can be reproduced very well by numerical simulations and interpreted as the superposition of the dipole and quadrupole modes with the help of analytic calculations. Moreover, we hypothesize that the electrons collected by PEEM are mainly from the plasmonic hot spots located at the plane in the interface between the Au particles and the substrate in the PEEM experiments. (C) 2017 Chinese Laser Press
  • Ryohei Takakura, Tomoya Oshikiri, Kosei Ueno, Xu Shi, Toshiaki Kondo, Hideki Masuda, Hiroaki Misawa
    GREEN CHEMISTRY 19 10 2398 - 2405 2017年05月 [査読有り][通常論文]
     
    In this study, we developed a three-dimensional plasmonic photoanode using titanium dioxide nanotunnels (TNTs) loaded with gold nanoparticles (Au-NPs) for water splitting, to enhance the reaction efficiency. We also optimized the procedure of loading Au-NPs on complex three-dimensional structures. We discuss the correlation between the plasmon-induced charge separation obtained from photoelectrochemical measurement and the morphology of Au-NPs observed by transmission electron microscopy. We have successfully deposited well-dispersed Au-NPs on the walls of TNTs using HAu(OH)(4) as a precursor. The amount of Au-NPs on the TNTs was estimated to be approximately 15-fold larger than that on the thin film titanium dioxide substrate, and the particle size remained small. Photoelectrochemical water splitting was achieved by using a two-electrode system rather than a three-electrode system. Furthermore, stoichiometric water splitting was confirmed by estimating the amounts of the evolved H-2 and O-2 gases under visible light irradiation.
  • Hidetoshi Mizobata, Kosei Ueno, Hiroaki Misawa, Hiromi Okamoto, Kohei Imura
    OPTICS EXPRESS 25 5 5279 - 5289 2017年03月 [査読有り][通常論文]
     
    We examine the far-field and near-field properties of complementary screens made of nanostructured gold thin films, a rectangular nanowire and a nanovoid, using an aperture-type scanning near-field optical microscope and electromagnetic field calculations, and discuss the applicability of Babinet's principle in the optical region. The far-field transmission spectra of the complementary screens are considerably different from each other. On the other hand, genuine near-field extinction spectra exhibit nearly complementary characteristics. The spatial features of the observed near-field images for the complementary screens show little correlation. We have found from the Fourier analysis of the simulated images that high spatial-frequency components of the electromagnetic fields show mutual spatial correlation. These results suggest that Babinet's principle is applicable to the high spatial-frequency components of electromagnetic fields for the complementary screens. (C) 2017 Optical Society of America
  • Han Yu, Quan Sun, Jinghuan Yang, Kosei Ueno, Tomoya Oshikiri, Atsushi Kubo, Yasutaka Matsuo, Qihuang Gong, Hiroaki Misawa
    OPTICS EXPRESS 25 6 6883 - 6894 2017年03月 [査読有り][通常論文]
     
    We investigated the grating effect in complex gold dolmen structures, in which multiple plasmon modes are present due to plasmon hybridization, experimentally from both the far field and the near field. In particular, the near-field properties were investigated using photoemission electron microscopy, and it was demonstrated that two hybridized plasmon modes on the dolmen structures could be influenced by the grating effect. For comparison, we also investigated the grating effect in arrays of simple nanoblocks and heptamer structures, which were supposed to support a strong bright plasmon mode and a strong dark plasmon mode, respectively, in the near field. We found that the spectral responses of the two hybridized modes on the dolmen structures as the pitch size changed evolved in a manner similar to that of the bright dipole mode on the nanoblocks, whereas the dark mode on the heptamer structures is less sensitive to the pitch size. (C) 2017 Optical Society of America
  • Kuang-Li Lee, Hsuan-Yeh Hsu, Meng-Lin You, Chia-Chun Chang, Ming-Yang Pan, Xu Shi, Kosei Ueno, Hiroaki Misawa, Pei-Kuen Wei
    SCIENTIFIC REPORTS 7 2017年03月 [査読有り][通常論文]
     
    Metallic nanostructure-based surface plasmon sensors are capable of real-time, label-free, and multiplexed detections for chemical and biomedical applications. Recently, the studies of aluminum-based biosensors have attracted a large attention because aluminum is a more cost-effective metal and relatively stable. However, the intrinsic properties of aluminum, having a large imaginary part of the dielectric function and a longer evanescent length, limit its sensing capability. Here we show that capped aluminum nanoslits fabricated on plastic films using hot embossing lithography can provide tailorable Fano resonances. Changing height of nanostructures and deposited metal film thickness modulated the transmission spectrum, which varied from Wood's anomaly-dominant resonance, asymmetric Fano profile to surface plasmon-dominant resonance. For biolayer detections, the maximum surface sensitivity occurred at the dip of asymmetric Fano profile. The optimal Fano factor was close to -1.3. The wavelength and intensity sensitivities for surface thickness were up to 2.58 nm/nm and 90%/nm, respectively. The limit of detection (LOD) of thickness reached 0.018 nm. We attributed the enhanced surface sensitivity for capped aluminum nanoslits to a reduced evanescent length and sharp slope of the asymmetric Fano profile. The protein-protein interaction experiments verified the high sensitivity of capped nanostructures. The LOD was down to 236 fg/mL.
  • Jingchun Guo, Tomoya Oshikiri, Kosei Ueno, Xu Shi, Hiroaki Misawa
    ANALYTICA CHIMICA ACTA 957 70 - 75 2017年03月 [査読有り][通常論文]
     
    We developed a localized surface plasmon-induced visible light-responsive photoelectrochemical (PEC) biosensor using a titanium dioxide (TiO2) photoelectrode loaded with gold nanoislands (AuNIs) for in situ real-time measurement of biotin-streptavidin association. As a proof of concept, self-assembled thiol-terminated biotin molecules bound on a AuNls/TiO2 photoelectrode were successfully utilized to explore the photocurrent response to streptavidin-modified gold nanoparticle (STA-AuNP) solutions. This plasmon-induced PEC biosensor is simple and easy to miniaturize. Additionally, the PEC biosensor achieves highly sensitive measurements under only visible light irradiation and prevents the UV-induced damage of samples. Furthermore, a novel approach has been proposed to realize the real-time monitoring of biotin-STA binding affinities and kinetics by analyzing the PEC sensing characteristics. This PEC biosensor and novel analysis method could provide a new approach for the specific electrical detection and real-time kinetic measurements for clinical diagnostics and drug development. (C) 2016 The Authors. Published by Elsevier B.V.
  • Kuang-Li Lee, Po-Cheng Tsai, Meng-Lin You, Ming-Yang Pan, Xu Shi, Kosei Ueno, Hiroaki Misawa, Pei-Kuen Wei
    ACS Omega 2 10 7461 - 7470 2017年 [査読有り][通常論文]
     
    The studies of nanostructure-based aluminum sensors have attracted huge attention because aluminum is a more cost-effective plasmonic material. However, the intrinsic properties of the aluminum metal, having a large imaginary part of the dielectric function and a longer electromagnetic field decay length and problems of poor long-term chemical stability, limit the surface-sensing capability and applicability of nanostructures. We propose the combination of capped aluminum nanoslits and a thin-capped dielectric layer to overcome these limitations. We show that the dielectric layer can positively enhance the wavelength sensitivities of the Wood's anomaly-dominant resonance and asymmetric Fano resonance in capped aluminum nanoslits. The maximum improvement can be reached by a factor of 3.5. Besides, there is an optimal layer thickness for the surface sensitivity because of the trade-off relationship between the refractive index sensitivity and decay length. We attribute the enhanced surface sensitivity to a reduced evanescent length, which is confirmed by the finite difference time-domain calculations. The protein-protein interaction experiments verify the high-surface sensitivity of the structures, and a limit of quantification (LOQ) of 1 pg/mL antibovine serum albumin is achieved. Such low-cost, highly sensitive aluminum-based nanostructures can benefit various sensing applications.
  • Ahmed Esmail Shalan, Tomoya Oshikiri, Hiroki Sawayanagi, Keisuke Nakamura, Kosei Ueno, Quan Sun, Hui-Ping Wu, Eric Wei-Guang Diau, Hiroaki Misawa
    NANOSCALE 9 3 1229 - 1236 2017年01月 [査読有り][通常論文]
     
    Plasmonics is a highly promising approach to enhancing the light-harvesting properties of hybrid organic/ inorganic perovskite solar cells. In the present work, our cells have a p-i-n inverted planar structure. An ultrathin NiO film with two different thicknesses of 5 and 10 nm prepared by a pulsed laser deposition process on an ITO substrate with a faceted and furrowed surface enabled the formation of a continuous and compact layer of well-crystallized CH3NH3PbI3 via an anti-solvent chlorobenzene process. The coverage mechanism of the NiO film on the ITO was clearly demonstrated through the J-V and external quantum efficiency (EQE) curves. Moreover, the results demonstrated that the gold nanoislands (Au NIs) increased the power conversion efficiency to 5.1%, almost double that of the samples without Au NIs. This result is due to the excitation of surface plasmons, which is characterized by strong scattering and enhancement of the electric field in the vicinity of the Au NIs loaded at the interface between the NiO and perovskite films. Additionally, we observed an enhancement of the EQE at wavelengths shorter than the plasmon resonance peak. In the current state, we speculate that the plasmoelectric potential effect is considered to be a good explanation of the photocurrent enhancement at the off-resonance region. Our work provides good guidance for the design and fabrication of solar-energy-related devices employing NiO electrodes and plasmonic Au NIs.
  • Ahmed Esmail Shalan, Sudhakar Narra, Tomoya Oshikiri, Kosei Ueno, Xu Shi, Hui-Ping Wu, Mahmoud~M. Elshanawany, Eric Wei-Guang Diau, Hiroaki Misawa
    Sustainable Energy Fuels Royal Society of Chemistry ({RSC}) 2017年 [査読有り][通常論文]
  • Ahmed Esmail Shalan, Tomoya Oshikiri, Sudhakar Narra, Mahmoud M. Elshanawany, Kosei Ueno, Hui-Ping Wu, Keisuke Nakamura, Xu Shi, Eric Wei-Guang Diau, Hiroaki Misawa
    ACS APPLIED MATERIALS & INTERFACES 8 49 33592 - 33600 2016年12月 [査読有り][通常論文]
     
    CoOx is a promising hole-extracting layer (HEL) for inverted planar perovskite solar cells with device configuration ITO/CoOx/CH3NH3PbI3/PCBM/Ag. The devices fabricated according to a simple solution procedure showed the best photovoltaic performance attaining power conversion efficiency (PCE) of 14.5% under AM 1.5 G 1 sun irradiation, which is significantly superior to those of materials fabricated with a traditional HEL such as PEDOT:PSS (12.2%), NiOx (10.2%), and CuOx (9.4%) under the same experimental conditions. We characterized the chemical compositions with XPS, crystal structures with XRD, and film morphology with SEM/AFM techniques. Photoluminescence (PL) spectra and the corresponding PL decays for perovskite deposited on varied HEL films were recorded to obtain the hole-extracting characteristics, for which the hole extracting times show the order CoOx (2.8 ns) < PEDOT:PSS (17.5 ns) < NiOx (22.8 ns) < CuOx (208.5 ns), consistent with the trend of their photovoltaic performances. The reproducibility and enduring stability of those devices were examined to show the outstanding long-term stability of the devices made of metal oxide HEL, for which the CoOx device retained PCE approximate to 12% for over 1000 h.
  • Han Yu, Quan Sun, Kosei Ueno, Tomoya Oshikiri, Atsushi Kubo, Yasutaka Matsuo, Hiroaki Misawa
    ACS NANO 10 11 10373 - 10381 2016年11月 [査読有り][通常論文]
     
    The extraordinary optical properties of coupled plasmonic nanostructures make these materials potentially useful in many applications; thus, they have received enormous attention in basic and applied research. Coupled plasmon modes have been characterized predominantly using far-field spectroscopy. In near-field spectroscopy, the spectral response of local field enhancement in coupled plasmonic nanostructures remains largely unexplored, especially experimentally. Here, we investigate the coupled gold dolmen nanostructures in the near field using photoemission electron microscopy, with wavelength tunable femtosecond laser pulses as an excitation source. The spatial evolution of near-field mapping of an individual dolmen structure with the excitation wavelength was successfully obtained. In the near field, we spatially resolved an anti-bonding mode and a bonding mode as the result of plasmon hybridization. Additionally, the quadrupole plasmon mode that could be involved in the formation of a Fano resonance was also revealed by spatially resolved near-field spectra, but it only contributed little to the total near-field enhancement. On the basis of these findings, we obtained a better understanding of the near-field nanostructures, where the plasmon hybridization and the plasmonic Fano resonance were mixed.
  • Kosei Ueno, Quan Sun, Masahiro Mino, Takumi Itoh, Tomoya Oshikiri, Hiroaki Misawa
    OPTICS EXPRESS 24 16 17728 - 17737 2016年08月 [査読有り][通常論文]
     
    Infrared light has received attention for sensor applications, including fingerprint spectroscopy, in the bioengineering and security fields. Surface plasmon physics enables the operation of a light harvesting optical antenna. Gold nanochains exhibit localized surface plasmon resonance (LSPR) in the infrared region with high frequency selectivity. However, a feasible design for optical antennae with a higher resonant efficiency and frequency selectivity as a function of structural design and periodicity is still unknown. In the present study, we investigated the relationship between the resonant efficiency and frequency selectivity as a function of the structural design of gold nanochains and explored structural periodicity for obtaining highly frequency-selective optical antennae. An optical antenna design with higher resonant efficiency is proposed on the basis of its efficient interaction with non-polarized light. (C) 2016 Optical Society of America
  • Jie Li, Kosei Ueno, Hiyori Uehara, Jingchun Guo, Tomoya Oshikiri, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY LETTERS 7 14 2786 - 2791 2016年07月 [査読有り][通常論文]
     
    We report on the spectral properties of strong coupling between the localized surface plasmon resonances (LSPRs) of aluminum (Al) nanostructures and tetraphenylporphyrin tetrasulfonic acid hydrate (TPPS) J-aggregates. Because of their wide spectral range of LSPR bands from ultraviolet to near-infrared wavelengths by controlling structural size, Al nanodisks can realize strong coupling with different excitons of TPPS J-aggregates. The Rabi splitting energies of the excitons based on Soret and Qbands are 300 and 180 meV, respectively. In addition to extinction spectrum, we have also measured an excitation spectrum to determine the essential absorption of the hybrid states and successfully confirmed a shoulder peak corresponding to a lower branch of hybrid states. In Al nanorod systems, strong coupling with two excitons can also be selectively induced by merely rotating the polarization of the incident light, which constituted a simple platform for the dynamic control of exciton/plasmon coupling states.
  • Yukie Yokota, Kosei Ueno, Hiroaki Misawa, Takuo Tanaka
    Photonics 3 2 2016年06月01日 [査読有り][通常論文]
     
    We designed and fabricated gold curvilinear nanorod periodical arrays using microfabrication techniques. The gold curvilinear nanorods had two distinct resonant peaks in the near-infrared region between 1630 nm and 3000 nm. Similar peak was observed in gold straight nanorods at specific lengths. At lengths identical to the arc length of the curvilinear nanorod, the peak was in the relative range of 3000 nm, which corresponds to the longitudinal plasmon mode (L-mode). At lengths identical to half of the arc length of the curvilinear nanorod, the peak was close to 1630 nm. Plasmon resonant peaks were tunable in the infrared region by changing the arc length of the curve, the line width, and distance between the curvilinear nanorods. In particular, when two curvilinear nanorods were closely packed in a range of less than 100 nm, the peak wavelength of curvilinear nanorod was shifted due to the plasmonic coupling of each mode.
  • Spectral response and spatial evolution of plasmonic near field in coupled gold nanostructures
    Han,Yu, Quan,Sun, Oshikiri,T, Ueno,Kosei, Kubo,Atsushi, Matsuo,Yasutaka, Misawa,Hiroaki
    日本化学会第96春季年会 予稿集 4E3-12  2016年03月 [査読無し][通常論文]
  • Tomoya Oshikiri, Kosei Ueno, Hiroaki Misawa
    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 55 12 3942 - 3946 2016年03月 [査読有り][通常論文]
     
    The generation of ammonia from atmospheric nitrogen and water using sunlight is a preferable approach to obtaining ammonia as an energy carrier and potentially represents a new paradigm for achieving a low-carbon and sustainable-energy society. Herein, we report the selective conversion of dinitrogen into ammonia through plasmon-induced charge separation by using a strontium titanate (SrTiO3) photoelectrode loaded with gold nanoparticles (Au-NPs) and a zirconium/zirconium oxide (Zr/ZrOx) thin film. We observed the simultaneous stoichiometric production of ammonia and oxygen from nitrogen and water under visible-light irradiation.
  • Keisuke Nakamura, Tomoya Oshikiri, Kosei Ueno, Yongming Wang, Yoshiomi Kamata, Yuki Kotake, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY LETTERS 7 6 1004 - 1009 2016年03月 [査読有り][通常論文]
     
    We have successfully fabricated all-solid-state plasmonic photoelectric conversion devices composed of titanium dioxide (TiO2)/nickel oxide (NiO) p-n junctions with gold nanoparticles (Au-NPs) as prototype devices for a plasmonic solar cell. The characteristics of the crystal structures and the photoelectric properties of the all-solid-state devices were demonstrated. We observed that the crystalline structure of the NiO thin film and the interfacial structure of TiO2/Au-NPs/NiO changed significantly during an annealing treatment. Furthermore, the photoelectric conversion devices exhibited plasmon-induced photocurrent generation in the visible-wavelength region. The photo current may result from plasmon-induced charge separation. The photoelectric conversion properties via plasmon-induced charge separation were strongly correlated with the morphology of the TiO2/Au-NPs/NiO interface. The long-term stability of the plasmonic photoelectric conversion device was found to be very high because a stable photocurrent was observed even after irradiation for 3 days.
  • Quan Sun, Han Yu, Kosei Ueno, Atsushi Kubo, Yasutaka Matsuo, Hiroaki Misawa
    ACS NANO 10 3 3835 - 3842 2016年03月 [査読有り][通常論文]
     
    Dipole and quadrupole modes are the two lowest orders of localized surface plasmon resonance (LSPR) eigenmodes in metallic nanoparticles. Of these two modes, the quadrupole mode is forbidden for symmetric metallic nanoparticles excited by linearly polarized light at normal incidence. Here, we demonstrate excitation of the quadrupole mode in symmetrical gold (Au) nanoblocks shined with s -polarized light at oblique incidence. In particular, we probe the near -field LSPR in Au nanoblocks using photoemission electron microscopy (PEEM) and find that at oblique incidence, the dipole and quadrupole modes can be selectively excited, in terms of near -field enhancement, by manipulating the light polarization state. More importantly, by time -resolved PEEM measurements, we experimentally demonstrate that the quadrupole mode in symmetrical Au nanoblocks has longer dephasing time than that of the dipole mode.
  • Kosei Ueno, Tomoya Oshikiri, Hiroaki Misawa
    CHEMPHYSCHEM 17 2 199 - 215 2016年01月 [査読有り][通常論文]
     
    Visible- and near-infrared-light-driven water splitting, which splits water molecules to generate hydrogen and oxygen gases, is a significant subject in artificial photosynthesis with the goal of achieving a low-carbon society. In recent years, considerable attention has been paid to studies on the development of a plasmon-induced water-splitting system responding to visible light. In this review, we categorized water-splitting systems as gold-nanoparticle-loaded semiconductor photocatalytic particles system and metallic-nanoparticles-loaded semiconductor photoelectrode systems, and introduce the latest studies according to these categories. Especially, we describe the studies that optimize a material or a structural design of metallic-nanoparticle-loaded semiconductor photoelectrodes and consider a whole water-splitting system, including a cathode design. Furthermore, we discuss important points when studying plasmon-induced water splitting, and we describe a methodology that enhances plasmon-induced water-splitting efficiency.
  • Exploring plasmonic hot spots and their dynamics by photoemission electron microscopy
    Quan,Sun, Han,Yu, Ueno,Kosei, Kubo,Atsushi, Matsuo,Yasutaka, Misawa,Hiroaki
    Pacifichem 2015 2015年12月 [査読無し][通常論文]
  • Fano resonances on gold nano dolmen structures probed by photoemission electron microscopy
    Han,Yu, Quan,Sun, Ueno,Kosei, Kubo,Atsushi, Matsuo,Yasutaka, Misawa,Hiroaki
    Pacifichem 2015 2015年12月 [査読無し][通常論文]
  • Kosei Ueno, Sho Nozawa, Hiroaki Misawa
    Optics Express 23 22 28584 - 28592 2015年11月02日 [査読有り][通常論文]
     
    Terahertz (THz) spectroscopy is a promising method to measure the spectrum of low-frequency modes of molecules or ensembles, such as crystals and polymers, including proteins. However, the main drawback of THz spectroscopy is its extremely low sensitivity. In the present study, we report on signal enhancement in THz spectroscopy achieved by depositing amino acid molecules or their derivatives on a gold rod structured silicon substrate whose localized surface plasmon resonance is exhibited in the THz frequency region. The distinct peaks derived from the enhancement of the inherent spectrum based on a molecular crystal were clearly observed when a longitudinal plasmon resonance mode of the gold rod structure was excited and the plasmon resonance band overlapped the molecular/intermolecular vibrational mode. We discuss the mechanism by which surface-enhanced THz spectroscopy was induced from the viewpoint of the enhancement of light-matter coupling due to plasmon excitation and the modulation of the plasmon band by dipole coupling between the plasmon dipole and molecular/intermolecular vibrational modes.
  • Kosei Ueno, Tomoya Oshikiri, Kei Murakoshi, Haruo Inoue, Hiroaki Misawa
    PURE AND APPLIED CHEMISTRY 87 6 547 - 555 2015年06月 [査読有り][通常論文]
     
    We have successfully demonstrated plasmon-enhanced photocurrent generation using gold nan-oparticle- loaded titanium dioxide single-crystal (TiO2) photoelectrodes with visible-light irradiation. Water molecules serve as an electron source in photocurrent generation, and oxygen evolution occurs due to water oxidation from a gold nanostructured TiO2 photoelectrode as a half reaction of water splitting. On the basis of this property, the photocurrent generation system was applied to the plasmon-induced water-splitting system using both sides of the same strontium titanate (SrTiO3) single-crystal substrate without an electrochemical apparatus. The chamber on the side of the gold nanoparticles was the anode side, whereas the chamber on the side of the platinum plate was the cathode side. Platinum was used as a co-catalyst for hydrogen evolution. Hydrogen and oxygen were separately evolved from the anode and cathode chambers, respectively. Water splitting was induced with a relatively low chemical bias of 0.23 V due to plasmonic effects based on efficient water oxidation. Similar to the artificial photosynthesis system, we have also demonstrated ammonia formation via nitrogen fixation using ruthenium as a co-catalyst via an analogous setup of the water-splitting system.
  • Kosei Ueno, Tomoya Oshikiri, Xu Shi, Yuqing Zhong, Hiroaki Misawa
    INTERFACE FOCUS 5 3 20140082  2015年06月 [査読有り][通常論文]
     
    We have successfully developed a plasmon-induced artificial photosynthesis system that uses a gold nanoparticle-loaded oxide semiconductor electrode to produce useful chemical energy as hydrogen and ammonia. The most important feature of this system is that both sides of a strontium titanate single-crystal substrate are used without an electrochemical apparatus. Plasmon-induced water splitting occurred even with a minimum chemical bias of 0.23 V owing to the plasmonic effects based on the efficient oxidation of water and the use of platinum as a co-catalyst for reduction. Photocurrent measurements were performed to determine the electron transfer between the gold nanoparticles and the oxide semiconductor. The efficiency of water oxidation was determined through spectroelectrochemical experiments aimed at elucidating the electron density in the gold nanoparticles. A set-up similar to the water-splitting system was used to synthesize ammonia via nitrogen fixation using ruthenium instead of platinum as a co-catalyst.
  • Yuqing Zhong, Kosei Ueno, Yuko Mori, Tomoya Oshikiri, Hiroaki Misawa
    CHEMISTRY LETTERS 44 5 618 - 620 2015年05月 [査読有り][通常論文]
     
    A plasmon-enhanced water splitting system using a gold nanostructured strontium titanate (SrTiO3) single-crystal photoelectrode with a titanium dioxide (TiO2) thin film heterojunction was developed. Simultaneous evolution of hydrogen and oxygen was observed in separate reaction chambers under visible light irradiation. The substrate composed of single-crystal SrTiO3 with a rutile TiO2 thin film heterojunction exhibited enhanced water splitting activity compared with the electrode without the TiO2 thin film because the synergistic effect may prevent the back-electron-transfer reaction.
  • Yuqing Zhong, Kosei Ueno, Yuko Mori, Tomoya Oshikiri, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY C 119 16 8889 - 8897 2015年04月 [査読有り][通常論文]
     
    We explored the performance of hydrogen (H-2) evolution using noble metals or their metal oxides as cocatalysts in the plasmon-induced water-splitting system. Although many studies have employed n-type semiconductor particle systems to investigate cocatalyst effects, evaluating only the catalytic activity of H-2 and oxygen (O-2) evolution has been limited by (1) the difficulty of transferring an electron injected into the conduction band of a semiconductor to a cocatalyst due to the formation of a Schottky barrier when a metallic cocatalyst for H2 evolution contacts the n-type semiconductor and (2) the potential for a reverse water-splitting reaction, which occurs due to the promotion of the reduction of the evolved O-2 by the cocatalyst. To overcome these limitations, in the present study, we eliminated the adverse effect of the Schottky barrier by obtaining ohmic contact between the semiconductor and the metal or metal oxide cocatalysts, and we used two separate reaction chambers for H-2 and O-2 evolution to avoid reverse water-splitting reactions such as H2O2 recombination or the photoreduction of O-2. A 23 nm thick rhodium layer deposited on a platinum board exhibited relatively high performance, a 3-fold increase compared with the absence of a metal or metal oxide cocatalyst thin layer.
  • Tomoya Oshikiri, Kosei Ueno, Hiroaki Misawa
    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 53 37 9802 - 9805 2014年09月 [査読有り][通常論文]
     
    We have successfully developed a plasmon-induced technique for ammonia synthesis that responds to visible light through a strontium titanate (SrTiO3) photoelectrode loaded with gold (Au) nanoparticles. The photoelectrochemical reaction cell was divided into two chambers to separate the oxidized (anodic side) and reduced (cathodic side) products. To promote NH3 formation, a chemical bias was applied by regulating the pHvalue of these compartments, and ethanol was added to the anodic chamber as a sacrificial donor. The quantity of NH3 formed at the ruthenium surface, which was used as a co-catalyst for SrTiO3, increases linearly as a function of time under irradiation with visible light at wavelengths longer than 550nm. The NH3 formation action spectrum approximately corresponds to the plasmon resonance spectrum. We deduced that plasmon-induced charge separation at the Au/SrTiO3 interface promotes oxidation at the anodic chamber and subsequent nitrogen reduction on the cathodic side.
  • Yuqing Zhong, Kosei Ueno, Yuko Mori, Xu Shi, Tomoya Oshikiri, Kei Murakoshi, Haruo Inoue, Hiroaki Misawa
    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 53 39 10350 - 10354 2014年09月 [査読有り][通常論文]
     
    A plasmon-induced water splitting system that operates under irradiation by visible light was successfully developed; the system is based on the use of both sides of the same strontium titanate (SrTiO3) single-crystal substrate. The water splitting system contains two solution chambers to separate hydrogen (H-2) and oxygen (O-2). To promote water splitting, a chemical bias was applied by regulating the pH values of the chambers. The quantity of H-2 evolved from the surface of platinum, which was used as a reduction co-catalyst, was twice the quantity of O-2 evolved from an Au-nanostructured surface. Thus, the stoichiometric evolution of H-2 and O-2 was clearly demonstrated. The hydrogen-evolution action spectrum closely corresponds to the plasmon resonance spectrum, indicating that the plasmon-induced charge separation at the Au/SrTiO3 interface promotes water oxidation and the subsequent reduction of a proton on the backside of the SrTiO3 substrate. The chemical bias is significantly reduced by plasmonic effects, which indicates the possibility of constructing an artificial photosynthesis system with low energy consumption.
  • Exploring quadrupole and higher order surface plasmon resonances in individual plasmonic nanoantennas by PEEM
    Q.,Sun, H.,Yu, K.,Ueno, Kubo,Atsushi, Y.,Matsuo, H.,Misawa
    LEEM/PEEM 9 Book of Abttracts 75 - 75 Forschungszentrum Jülich GmbH 2014年09月 [査読無し][通常論文]
  • Bin-Bin Xu, Lei Wang, Zhuo-Chen Ma, Ran Zhang, Qi-Dai Chen, Chao Lv, Bing Han, Xin-Ze Xiao, Xu-Lin Zhang, Yong-Lai Zhang, Kosei Ueno, Hiroaki Misawa, Hong-Bo Sun
    ACS NANO 8 7 6682 - 6692 2014年07月 [査読有り][通常論文]
     
    We report polarized femtosecond laser-light-mediated growth and programmable assembly of photoreduced silver nanoparticles into triply hierarchical micropatterns. Formation of erected arrays of nanoplates with a thickness as small as lambda/27 (lambda, the writing laser wavelength) level is demonstrated. The growth mechanism of nanoplates has been clarified: (i) the excited surface plasmons enhance the local electric field and lead to spatially selective growth of silver atoms at the opposite ends of dipoles induced on early created silver seeds; (ii) the optical attractive force overcomes electrostatic repulsion in the enhanced local electric field to assemble the silver nanoparticles directly. The triply hierarchical micropattern shape and location, the nanoplate orientation, and thickness are all attained in controlled fashion.
  • Olivier Lecarme, Quan Sun, Kosei Ueno, Hiroaki Misawa
    ACS PHOTONICS 1 6 538 - 546 2014年06月 [査読有り][通常論文]
     
    We investigate the far-field and near-field properties of aluminum nanorods fabricated by electron beam lithography and exhibiting plasmonic resonance in the near-infrared region. First, we show that plasmonic modes within nanorod arrays can be tuned by geometrical parameters, allowing one to control the system transparency. Next, the light absorption in this structure is closely examined, and we demonstrate that aluminum has great potential due to its unique interband transition at 800 nm. The roles of the dielectric confinement and the coupling between plasmonic resonance and the interband transition are particularly emphasized, as their adjustment can be used to switch from highly scattering particles to absorbing particles without a significant modification of the plasmonic resonance position. Finally, we image the plasmon-generated local field distribution in the aluminum nanostructures and observe, for the first time, the effect of the interband transition on the near-field behavior. The effect of the dielectric confinement is also numerically investigated, as it is shown to play a significant role in near-field enhancement.
  • K. Imura, K. Ueno, H. Misawa, H. Okamoto, D. McArthur, B. Hourahine, F. Papoff
    OPTICS EXPRESS 22 10 12189 - 12199 2014年05月 [査読有り][通常論文]
     
    Optical properties of single gold nanodiscs were studied by scanning near-field optical microscopy. Near-field transmission spectra of a single nanodisc exhibited multiple plasmon resonances in the visible to near-infrared region. Near-field transmission images observed at these resonance wavelengths show wavy spatial features depending on the wavelength of observation. To clarify physical pictures of the images, theoretical simulations based on spatial correlation between electromagnetic fundamental modes inside and outside of the disc were performed. Simulated images reproduced the observed spatial structures excited in the disc. Mode-analysis of the simulated images indicates that the spatial features observed in the transmission images originate mainly from a few fundamental plasmon modes of the disc. (C) 2014 Optical Society of America
  • Revealing higher order surface plasmon resonances and their dynamics by PEEM
    Quan,Sun, Han,Yu, Kosei,Ueno, Kubo,Atsushi, Yasutaka,Matsuo, Hiroaki,Misawa
    第61回応用物理学会春季学術講演会 講演予稿集 2014年03月 [査読無し][通常論文]
  • Anri Watanabe, Yuki Kotake, Yoshiomi Kamata, Akira Chikamatsu, Kosei Ueno, Hiroaki Misawa, Tetsuya Hasegawa
    JOURNAL OF PHYSICAL CHEMISTRY LETTERS 5 1 25 - 29 2014年01月 [査読有り][通常論文]
     
    The use of localized surface plasmon resonance induced by Ag nanostructures is a promising way for high-efficiency photoelectric conversion. In plasmonic photoelectric conversion devices, however, the chemical instability of Ag in ambient atmosphere and its immediate deterioration have been a critical issue. Here, we propose a Ag-Co nanostructure array embedded in a TiO2 matrix as a plasmonic resonator that ensures long-term stability. We also developed an electrochemical process to remove surface Co nanoclusters protecting fresh Ag from exposure to air. This enabled us to "unseal" Ag at the desired time. Furthermore, we confirmed photoelectric conversion using Ag-Co-TiO2 nanocomposite films in contact with solution; the photoelectric conversion was substantially enhanced by the plasmon resonance of the Ag nanorods. The Ag nanostructures sealed in a TiO2 matrix are expected to be used in other application fields, such as catalytisis and sensing, in which a fresh Ag surface is needed.
  • Gang Bi, Li Wang, Chunfeng Cai, Kosei Ueno, Hiroaki Misawa, Jianrong Qiu
    JOURNAL OF MODERN OPTICS 61 15 1231 - 1235 2014年 [査読有り][通常論文]
     
    The periodic arrays of gold nanocylinder with 121 nm in diameter, 6.3 nm in gap, and 34 nm in thickness are fabricated on glass by electron-beam lithography and lift-off techniques. Some crystal violet molecules are coated on the array by using the dipping and drawing method. In addition, the surface-enhanced Raman scattering (SERS) spectra of these samples with and without gold nanocylinder arrays are characterized specifically. The largest enhancement factor is obtained when the excitation wavelength corresponds to the peak wavelength of localized surface plasmon resonance (LSPR). The density functional theory and the finite-difference time-domain method are used for the calculations of the extinction spectrum of the arrays and Raman spectra of the crystal violet, respectively. These results unambiguously demonstrate that the periodic arrays of gold nanocylinder have good and effective surface-enhanced properties for Raman scattering of crystal violets, and they also show that the excitation wavelength corresponding to the peak one of the LSPR is one of the major reasons causing SERS.
  • Quan Sun, Kosei Ueno, Han Yu, Atsushi Kubo, Yasutaka Matsuo, Hiroaki Misawa
    LIGHT-SCIENCE & APPLICATIONS 2 e118  2013年12月 [査読有り][通常論文]
     
    Localized surface plasmon resonance (LSPR) can be supported by metallic nanoparticles and engineered nanostructures. An understanding of the spatially resolved near-field properties and dynamics of LSPR is important, but remains experimentally challenging. We report experimental studies toward this aim using photoemission electron microscopy (PEEM) with high spatial resolution of sub-10 nm. Various engineered gold nanostructure arrays (such as rods, nanodisk-like particles and dimers) are investigated via PEEM using near-infrared (NIR) femtosecond laser pulses as the excitation source. When the LSPR wavelengths overlap the spectrum of the femtosecond pulses, the LSPR is efficiently excited and promotes multiphoton photoemission, which is correlated with the local intensity of the metallic nanoparticles in the near field. Thus, the local field distribution of the LSPR on different Au nanostructures can be directly explored and discussed using the PEEM images. In addition, the dynamics of the LSPR is studied by combining interferometric time-resolved pump-probe technique and PEEM. Detailed information on the oscillation and dephasing of the LSPR field can be obtained. The results identify PEEM as a powerful tool for accessing the near-field mapping and dynamic properties of plasmonic nanostructures.
  • Quan Sun, Kosei Ueno, Han Yu, Atsushi Kubo, Yasutaka Matsuo, Hiroaki Misawa
    LIGHT-SCIENCE & APPLICATIONS 2 2013年12月 [査読有り][通常論文]
     
    Localized surface plasmon resonance (LSPR) can be supported by metallic nanoparticles and engineered nanostructures. An understanding of the spatially resolved near-field properties and dynamics of LSPR is important, but remains experimentally challenging. We report experimental studies toward this aim using photoemission electron microscopy (PEEM) with high spatial resolution of sub-10 nm. Various engineered gold nanostructure arrays (such as rods, nanodisk-like particles and dimers) are investigated via PEEM using near-infrared (NIR) femtosecond laser pulses as the excitation source. When the LSPR wavelengths overlap the spectrum of the femtosecond pulses, the LSPR is efficiently excited and promotes multiphoton photoemission, which is correlated with the local intensity of the metallic nanoparticles in the near field. Thus, the local field distribution of the LSPR on different Au nanostructures can be directly explored and discussed using the PEEM images. In addition, the dynamics of the LSPR is studied by combining interferometric time-resolved pump-probe technique and PEEM. Detailed information on the oscillation and dephasing of the LSPR field can be obtained. The results identify PEEM as a powerful tool for accessing the near-field mapping and dynamic properties of plasmonic nanostructures.
  • Quan Sun, Kosei Ueno, Han Yu, Atsushi Kubo, Yasutaka Matsuo, Hiroaki Misawa
    LIGHT-SCIENCE & APPLICATIONS 2 2013年12月 [査読有り][通常論文]
     
    Localized surface plasmon resonance (LSPR) can be supported by metallic nanoparticles and engineered nanostructures. An understanding of the spatially resolved near-field properties and dynamics of LSPR is important, but remains experimentally challenging. We report experimental studies toward this aim using photoemission electron microscopy (PEEM) with high spatial resolution of sub-10 nm. Various engineered gold nanostructure arrays (such as rods, nanodisk-like particles and dimers) are investigated via PEEM using near-infrared (NIR) femtosecond laser pulses as the excitation source. When the LSPR wavelengths overlap the spectrum of the femtosecond pulses, the LSPR is efficiently excited and promotes multiphoton photoemission, which is correlated with the local intensity of the metallic nanoparticles in the near field. Thus, the local field distribution of the LSPR on different Au nanostructures can be directly explored and discussed using the PEEM images. In addition, the dynamics of the LSPR is studied by combining interferometric time-resolved pump-probe technique and PEEM. Detailed information on the oscillation and dephasing of the LSPR field can be obtained. The results identify PEEM as a powerful tool for accessing the near-field mapping and dynamic properties of plasmonic nanostructures.
  • Xu Shi, Kosei Ueno, Tomoya Oshikiri, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY C 117 47 24733 - 24739 2013年11月 [査読有り][通常論文]
     
    In this study, we demonstrated an improvement in the plasmon-enhanced photocurrent generation due to Fabry-Perot interference of titanium dioxide (TiO2) thin-film electrodes loaded with Au nanoislands (Au-NIs). TiO2 thin films with thicknesses of 215-274 nm, which show obvious Fabry-Perot interference, were deposited via atomic layer deposition (ALD) onto silica glass and were modified by the deposition of Au-NIs onto their surface. Anodic plasmon-enhanced photocurrent generation was observed over the Au-NIs-loaded TiO2 thin-film photoelectrodes. The incident photon to current efficiency (IPCE) action spectra correlated strongly with the Au-NIs plasmon resonance and exhibited a strong dependence on the thickness of the TiO2 thin film. The photocurrent conversion efficiency increased when the transmission constructive interference wavelength overlapped with the Au-NIs plasmon resonance band. This work provides a simple and applicable approach for the further design of low-cost and lightweight plasmon-enhanced energy conversion devices.
  • Kosei Ueno, Hiroaki Misawa
    NPG ASIA MATERIALS 5 e61 2013年09月 [査読有り][通常論文]
     
    This paper presents recent investigations of plasmon-enhanced photoelectric conversion and water oxidation by visible and near-infrared light irradiation. Since the discovery of the Honda-Fujishima effect in 1972, significant efforts have been devoted to lengthening the light-energy conversion wavelength. In this context, plasmonic photoelectric conversion has been recently demonstrated at visible-to-near-infrared wavelengths without deteriorating photoelectric conversion by employing titanium dioxide (TiO2) single-crystal photoelectrodes, in which gold nanorods are elaborately arrayed on the surface. A potassium perchlorate aqueous solution was employed as an electrolyte solution without additional electron donors; thus, water molecules provided the electrons. The stoichiometric evolution of oxygen and hydrogen peroxide as a result of the four-or two-electron oxidation of water molecules, respectively, was accomplished with near-infrared light irradiation using the plasmonic optical antenna effect. As there is very little overpotential for water oxidation, these results constitute a significant advancement in this field. In addition, this photoelectric conversion system could potentially be employed in artificial photosynthesis systems that exceed the photosynthetic capabilities of plants by allowing for photoconversion over a wide range of wavelengths.
  • Kosei Ueno, Hiroaki Misawa
    Journal of Photochemistry and Photobiology C: Photochemistry Reviews 15 1 31 - 52 2013年06月 [査読有り][通常論文]
     
    The electromagnetic field enhancement effect based on the excitation of localized surface plasmon resonance was developed for various photochemical reaction systems, such as nano-lithography, photovoltaic cells, photocatalysis, and water splitting systems. As with most points characteristic of these surface plasmon-enhanced photochemical reactions, spatially selective photochemical reactions can be induced and photons can be efficiently utilized, a concept that could contribute to the development of green nanotechnology. Electromagnetic field enhancement effects based on plasmon excitation have contributed not only to physical processes, such as excitation efficiency, but also to chemical processes, such as photo-induced electron transfer reactions. This review article describes advanced studies on a wide variety of surface plasmon-enhanced photochemical reactions. © 2013 Elsevier B.V.
  • Gang Bi, Li Wang, Li Ling, Yukie Yokota, Yoshiaki Nishijima, Kosei Ueno, Hiroaki Misawa, Jianrong Qiu
    Optics Communications 294 213 - 217 2013年05月01日 [査読有り][通常論文]
     
    Gold-bowtie nanostructures are fabricated by electron beam lithography and lift-off techniques. Their optical properties are investigated by both experimental studies and numerical simulations. The influence of sharpness and gap of nano-bowtie on optical properties such as extinction cross section, local electric field intensity, and surface resonance wavelength is explored. The experimental extinction spectra agree well with the simulation results. This investigation may help us to design plasmonic sub-wavelength gold-bowtie nanostructure with desired spectral properties. © 2013 Elsevier B.V.
  • Kosei Ueno, Hiroaki Misawa
    Physical Chemistry Chemical Physics 15 12 4093 - 4099 2013年03月28日 [査読有り][通常論文]
     
    Plasmonic chemistry, a new research field dedicated to understanding plasmon-enhanced photochemical reactions, has become a principal area of chemical research, especially in the field of physical chemistry. In this perspective review article, we describe our recent research regarding the development of a fabrication methodology for metallic nanostructures that exhibit localized surface plasmon resonance, the spectral properties of the fabricated metallic nanostructures and their electromagnetic field enhancement effects using two-photon-induced photoluminescence from gold nanoparticles. © 2013 the Owner Societies.
  • Near Infrared Fluorescence Enhancement by Local Surface Plasmon Resonance from Arrayed Gold Nanoblocks
    F. Ito, R. Ohta, Y. Yokota, K. Ueno, H. Misawa, T. Nagamura
    Optics and Photonics Journal 3 27 - 31 2013年03月 [査読有り][通常論文]
  • Xu Shi, Kosei Ueno, Naoki Takabayashi, Hiroaki Misawa
    Journal of Physical Chemistry C 117 6 2494 - 2499 2013年02月14日 [査読有り][通常論文]
     
    Metallic nanoparticles showing localized surface plasmon resonance (LSPR) are efficient elements in the localization of light to nanometer-scale regions and enhance the light-matter interaction. We show that gold nanoisland (Au-NI)-loaded titanium dioxide (TiO2) photoelectrodes exhibited plasmon-enhanced photocurrent generation in the visible wavelength region, and the photocurrent action spectrum was corresponding to the LSPR band. The photocurrent enhancement may result from the plasmon-assisted electron transfer reaction from Au-NI to TiO2. A hole with high oxidation ability was left at the TiO2 surface states near the Au-NIs/TiO2 interface, which has the potential for photocatalytic water oxidation. The photocurrent generation efficiency of Au-NIs/TiO2 photoelectrode is highly dependent on the annealing temperature for the preparation of Au-NIs. High-resolution transmission electron microscopy and electron energy-loss spectroscopy analyses show that the interfacial structure between Au-NI and TiO2 plays a crucial role in the photocurrent generation efficiency and photocatalytic ability. © 2012 American Chemical Society.
  • Hiroaki Misawa, Hideki Masuda, Sunao Yamada, Kei Murakoshi
    JOURNAL OF PHYSICAL CHEMISTRY C 117 6 2433 - 2434 2013年02月 [査読有り][通常論文]
  • Kohei Imura, Kosei Ueno, Hiroaki Misawa, Hiromi Okamoto
    JOURNAL OF PHYSICAL CHEMISTRY C 117 6 2449 - 2454 2013年02月 [査読有り][通常論文]
     
    We studied optical properties of single elongated rectangular nanovoids opened on a thin gold film by scanning near-field optical microscopy. We found that the luminescence is induced via two-photon absorption of near-infrared pulses when the sample is locally photoexcited inside the void as well as on the film. The luminescence spectrum of the void shows spectral features very similar to those observed for gold nanorods and is attributable to that from gold. On the basis of the near-field two-photon excitation imaging by detecting the luminescence, we visualized the optical fields near the voids. The optical image shows a characteristic spatial feature depending on the dimension of the void. From the dose inspection of the topography and the optical images, we found that excitation probability becomes high at the metal void boundary as well as inside the void. We found an oscillating feature along the long axis of the void. The observed spatial features were qualitatively reproduced by photonic local density-of-states based on electromagnetic calculations, and we conduded that the oscillation observed inside the void is attributed to the electromagnetic modes in the void coupled with the plasmon excitations.
  • Tatsuya Konishi, Manabu Kiguchi, Mai Takase, Fumika Nagasawa, Hideki Nabika, Katsuyoshi Ikeda, Kohei Uosaki, Kosei Ueno, Hiroaki Misawa, Kei Murakoshi
    Journal of the American Chemical Society 135 3 1009 - 1014 2013年01月23日 [査読有り][通常論文]
     
    The in situ observation of geometrical and electronic structural dynamics of a single molecule junction is critically important in order to further progress in molecular electronics. Observations of single molecular junctions are difficult, however, because of sensitivity limits. Here, we report surface-enhanced Raman scattering (SERS) of a single 4,4′-bipyridine molecule under conditions of in situ current flow in a nanogap, by using nano-fabricated, mechanically controllable break junction (MCBJ) electrodes. When adsorbed at room temperature on metal nanoelectrodes in solution to form a single molecule junction, statistical analysis showed that nontotally symmetric b1 and b2 modes of 4,4′-bipyridine were strongly enhanced relative to observations of the same modes in solid or aqueous solutions. Significant changes in SERS intensity, energy (wavenumber), and selectivity of Raman vibrational bands that are coincident with current fluctuations provide information on distinct states of electronic and geometrical structure of the single molecule junction, even under large thermal fluctuations occurring at room temperature. We observed the dynamics of 4,4′-bipyridine motion between vertical and tilting configurations in the Au nanogap via b1 and b2 mode switching. A slight increase in the tilting angle of the molecule was also observed by noting the increase in the energies of Raman modes and the decrease in conductance of the molecular junction. © 2012 American Chemical Society.
  • K. Ueno, H. Misawa
    ADVANCED FABRICATION TECHNOLOGIES FOR MICRO/NANO OPTICS AND PHOTONICS VI 8613 2013年 [査読有り][通常論文]
     
    Nanoparticles of noble metals show localized surface plasmon resonance. Plasmon resonances which are collective oscillations of conduction electrons give rise to the enhancement of electromagnetic field to the local surface of metallic nanoparticles. Therefore, various plasmonic near-field lithography systems were proposed so far. Here, we report on a plasmon-assisted nanolithography used for the fabrication of nano-patterns with nanometric accuracy. The lithography system can form deep nano-patterns on positive photoresist film using scattering component of multipole plasmon resonances as an exposure light. Two-photon-induced reaction of a photoresist enabled the formation of fine patterns even using plasmonic scattering light.
  • Yu Teng, Kosei Ueno, Xu Shi, Daisuke Aoyo, Jianrong Qiu, Hiroaki Misawa
    ANNALEN DER PHYSIK 524 11 733 - 740 2012年11月 [査読有り][通常論文]
     
    The authors report on surface plasmon-enhanced fluorescence of Eosin Y molecules induced by gold nanostructures. Al2O3 films deposited by atomic layer deposition with sub-nanometer resolution were used as the spacer layer to control the distance between molecules and the gold surface. As the thickness of the Al2O3 film increased, the fluorescence intensity first increased and then decreased. The highest enhancement factor is achieved with a 1 nm Al2O3 film. However, the trend for the fluorescence lifetime is the opposite. It first decreased and then increased. The changes in the fluorescence quantum yield were also calculated. The yield shows a similar trend to the fluorescence intensity. The competition between the surface plasmon-induced increase in the radiative decay rate and the gold-induced fluorescence quenching is responsible for the observed phenomenon. In addition, this competition strongly depends on the thickness of the spacer layer between Eosin Y molecules and the gold surface.
  • Kuang-Li Lee, Min-Jian Chih, Xu Shi, Kosei Ueno, Hiroaki Misawa, Pei-Kuen Wei
    ADVANCED MATERIALS 24 35 OP253 - OP259 2012年09月 [査読有り][通常論文]
  • Gang Bi, Li Wang, Wei Xiong, Kosi Ueno, Hiroaki Misawa, Jianrong Qiu
    CHINESE OPTICS LETTERS 10 9 092401  2012年09月 [査読有り][通常論文]
     
    We experimentally verify that surface plasmon (SP) enhances the photoluminescence (PL) of visible light from Tb3+-doped 60SiO(2)-20Al(2)O(3)-20CaF(2):0.3Tb(3+), 20Yb(3+) glass ceramics by using electron beam lithography to fabricate silver nanoparticles on the surface of the glass ceramics. Numerical calculation for the SP enhancement spectroscopy is achieved by using the finite-difference time-domain algorithm. A PL enhancement of Tb3+ by as much as 1.6 times is observed. The PL enhancement is mainly due to the coupling of excitation from F-7(6) to D-5(4) transition dipole of Tb3+ ion with SP mode induced from the silver nanoparticles.
  • Kosei Ueno, Hiroaki Misawa
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 85 8 843 - 853 2012年08月 [査読有り][通常論文]
     
    We used metallic nanoparticles exhibiting localized surface plasmon resonance and electromagnetic (EM) field enhancement effects induced by plasmon excitation for the photochemical reaction field; this approach makes it possible to increase the probability of an interaction between photons and the materials. EM field enhancement effects induced by gold nanostructures were elucidated using two-photon-induced photoluminescence from nanogap-spaced gold nanoparticles. The photoluminescence was promoted mainly in the surface regions of the gold nanoblocks adjacent to the nanogaps due to the EM field enhancement effect. To elucidate the near-field intensity distribution of the nanogap gold structures, we investigated the photopolymerization of a commercially available negative photoresist assisted by EM field enhancement in the nanogaps separating the gold nanoblocks. Photopolymerization rates were enhanced by several orders of magnitude in the gold nanoblock structures that contained nanogaps narrower than 10 nm. We propose two surface plasmon-assisted nanolithography techniques based on spatially selective photochemical reactions promoted by the EM field enhancement effect. The first method uses ultimate near-field lithography with a local near-field distribution induced in the nanogaps, and the second technique uses the scattering component of multipole plasmon resonance as an exposure mechanism. These lithographic techniques represent a type of application based on plasmon-enhanced chemical reactions.
  • Li Wang, Yoshiaki Nishijima, Kosei Ueno, Hiroaki Misawa, Naoto Tamai
    JOURNAL OF PHYSICAL CHEMISTRY C 116 33 17838 - 17846 2012年08月 [査読有り][通常論文]
     
    We examined the vibrational dynamics of periodic gold pair nanocuboids with various nanogaps and various pair-to-pair separations under 400 nm excitation by near-IR transient absorption spectroscopy. Multi-oscillation behavior of the coherent acoustic phonon vibration was observed for all the gold pair nanocuboid arrays. Two symmetric breathing modes were assigned to the displacement of edge-to-edge and its second harmonic, and the displacement of tip-to-tip of gold nanocuboids. We assigned the driving mechanisms of the edge-to-edge and the tip-to-tip modes to thermal expansion and hot-electron pressure, respectively, due to the different amplitudes and the phase mismatch between both modes. Moreover, Young's modulus of gold nanocuboids was estimated to be 97 GPa by using the measured vibrational periods of the edge mode. A little deviation from the bulk value (78 GPa) was interpreted in terms of an interaction of a gold nanocuboid with a substrate. In addition, the oscillation periods and damping constants of the phonon vibration were similar for all of the arrays, even though localized surface plasmon resonance (LSPR) bands were shifted due to near- and far-field dipole couplings. This phenomenon suggested that the phonon vibration was only influenced by the intrinsic properties of the nanomaterials. Furthermore, the oscillation amplitudes of the bleaching peaks exponentially decayed with the increase of the nanogap. We calculated the LSPR bands of gold pair nanocuboids with structural deformation by finite-difference time-domain simulation, and the estimated spectral shift was in good agreement with the experimental results.
  • Tobias Geldhauser, Andreas Kolloch, Naoki Murazawa, Kosei Ueno, Johannes Boneberg, Paul Leiderer, Elke Scheer, Hiroaki Misawa
    LANGMUIR 28 24 9041 - 9046 2012年06月 [査読有り][通常論文]
     
    The quantitative determination of the strength of the near-field enhancement in and around nanostructures is essential for optimizing and using these structures for applications. We combine the Gaussian intensity distribution of a laser profile and two-photon-polymerization of SU-8 to a suitable tool for the quantitative experimental measurement of the near-field enhancement of a nanostructure. Our results give a feedback to the results obtained by finite-difference rime-domain (FDTD) simulations. The structures under investigation are gold nanotriangles on a glass substrate with 85 nm side length and a thickness of 40 nm. We compare the threshold fluence for polymerization for areas of the Gaussian intensity profile with and without the near-field enhancement of the nanostructures. The experimentally obtained value of the near-field intensity enhancement is 600 140, independent of the laser power, irradiation time, and spot size. The FDTD simulation shows a pointlike maximum of 2600 at the tip. In a more extended area with an approximate size close to the smallest polymerized structure of 25 nm in diameter, we find a value between 800 and 600. Using our novel approach, we determine the threshold fluence for polymerization of the commercially available photopolymerizable resin SU-8 by a femtosecond laser working at a wavelength of 795 nm and a repetition rate of 82 MHz to be 0.25 J/cm(2) almost independent of the irradiation time and the laser power used. This finding is important for future applications of the method because it enables one to use varying laser systems.
  • Botao Wu, Kosei Ueno, Yukie Yokota, Kai Sun, Heping Zeng, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY LETTERS 3 11 1443 - 1447 2012年06月 [査読有り][通常論文]
     
    We performed a quantitative analysis of plasmon-assisted two-photon photochromic reactions on light-harvesting gold nanodimer structures. Our strategy for the quantitative analysis of two-photon-induced photochemical reactions on gold nanostructures is using not only a confined photochemical reaction chamber but also a solution system. The strong intensification of near-field light at the nanogap positions on gold nanodimer pairs promoted two-photon absorption by a closed-form diarylethene derivative, resulting in highly efficient photochromic conversion to the open-form structure.
  • Junjie Miao, Yongsheng Wang, Chuanfei Guo, Ye Tian, Jianming Zhang, Qian Liu, Zhiping Zhou, Hiroaki Misawa
    PLASMONICS 7 2 377 - 381 2012年06月 [査読有り][通常論文]
     
    In this paper, we study the nanoscale-focusing effect in the far field for a spiral plasmonic lens with a concentric annular groove by using finite-difference time domain simulation. The simulation result demonstrates that a left-hand spiral plasmonic lens can concentrate an incident right-hand circular polarization light into a focal spot at the exit surface. And this spot can be focused into far field due to constructive interference of the scattered light by the annular groove. The focal length and the focal depth can be adjusted by changing the groove radius and number of grooves within a certain range. These properties make it possible to probe the signal of spiral plasmonic lens in far field by using conventional optical devices.
  • Gang Bi, Wei Xiong, Li Wang, Kosei Ueno, Hiroaki Misawa, Jian-rong Qiu
    OPTICS COMMUNICATIONS 285 9 2472 - 2477 2012年05月 [査読有り][通常論文]
     
    This paper presents optical property of the periodical bowties structure of Au nanoparticles on glass substrate fabricated by high-resolution electron beam lithography. Numerical calculation is used to examine the shape-induced surface plasmon enhancement and extinction spectroscopy by using Finite-Difference Time Domain algorithm and Lorentz model of surface plasmon. The calculated extinction spectra of the periodical nanoparticles are consistent with the experimental results. The influence of the geometrical shape on the spectral properties of bowtie nanoparticles is discussed. This investigation may help one to design plasmonic sub-wavelength devices with desired spectral properties. (C) 2012 Elsevier B.V. All rights reserved.
  • Jun Sakai, Daniel Roldan, Kosei Ueno, Hiroaki Misawa, Yoichiroh Hosokawa, Takanori Iino, Shigeyuki Wakitani, Mutsumi Takagi
    CYTOTECHNOLOGY 64 3 323 - 329 2012年05月 [査読有り][通常論文]
     
    The effect of femtosecond laser irradiation on adherent mesenchymal stem cell was investigated with the aim to develop a novel noninvasive cell purification system. A single mesenchymal stem cell was irradiated with a femtosecond laser on the center of the cell using several energy values and the cell lost its replication capacity with one time irradiation with an energy of 2.0 mu J. Besides at a neighbor point in the major axis, when irradiated in the minor axis at a distance shorter than 10 mu m, the cell stopped its replication capacity. The accumulation effect of cell damage caused by multiple laser shots at a neighbor point in the minor axis was correlated with the critical distance at which the cell lost its replication capacity. Finally, a novel equation of laser cell damage as a function of laser pulse energy and laser shot number is proposed.
  • Yoshiaki Nishijima, Kosei Ueno, Yuki Kotake, Kei Murakoshi, Haruo Inoue, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY LETTERS 3 10 1248 - 1252 2012年05月 [査読有り][通常論文]
     
    We report the stoichiometric evolution of oxygen via water oxidation by irradiating a plasmon-enhanced photocurrent generation system with near-infrared light (lambda: 1000 am), in which gold nanostructures were arrayed on the surface of TiO2 electrode. It is considered that multiple electron holes generated by plasmon-induced charge excitation led to the effective recovery of water oxidation after the electron transfer from gold to TiO2. The proposed system containing a gold nanostructured TiO2 electrode may be a promising artificial photosynthetic system using near-infrared light.
  • Kita, Shota, Otsuka, Shota, Hachuda, Shoji, Endo, Tatsuro, Imai, Yasunori, Nishijima, Yoshiaki, Misawa, Hiroaki, Baba, Toshihiko
    IEICE TRANSACTIONS ON ELECTRONICS E95C 2 188 - 198 2012年02月 [査読有り][通常論文]
     
    High-performance and low-cost sensors are critical devices for high-throughput analyses of bio-samples in medical diagnoses and life sciences. In this paper, we demonstrate photonic crystal nanolaser sensor, which detects the adsorption of biomolecules from the lasing wavelength shift. It is a promising device, which balances a high sensitivity, high resolution, small size, easy integration, simple setup and low cost. In particular with a nanoslot structure, it achieves a super-sensitivity in protein sensing whose detection limit is three orders of magnitude lower than that of standard surface-plasmon-resonance sensors. Our investigations indicate that the nanoslot acts as a protein condenser powered by the optical gradient force, which arises from the strong localization of laser mode in the nanoslot.
  • Quan Sun, Kosei Ueno, Hiroaki Misawa
    OPTICS LETTERS 37 4 710 - 712 2012年02月 [査読有り][通常論文]
     
    We report on experimental study of the shrinkage of photopolymerized micro/nanostructures fabricated by femto-second direct laser writing in organic-inorganic resists. Blueshift of the stop-band positions of fabricated photonic crystals during the drying process, which follows the development and rinsing stages, indicates that the drying process plays an important role in the formation of the shrinkage. It is further confirmed that the shrinkage almost completely occurs during the drying process by in situ optical monitoring the structures. These findings will help to better understand, control, and even positively utilize the shrinkage in the applications of the photopolymerization-based direct laser writing technique. (C) 2012 Optical Society of America
  • K. Ueno, H. Misawa
    LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING (LAMOM) XVII 8243 2012年 [査読有り][通常論文]
     
    Advanced lithography systems, such as ArF immersion lithography, have achieved a 32 nm node(1,2) and are already used in electronic device development. However, the advanced lithography systems are not suitable for fabricating nanostructures, such as rectangular cuboids, triangular prisms, chains, and nanogaps. These nanostructures are being used for various applications that include plasmonic solar cells(3-5) and photonic crystal lasers. (6, 7) In this proceeding, we report an innovative lithography system appropriate for fabricating such nano-patterns with nanometric accuracy based on plasmon-assisted photolithography. The key technology is the two-photon photochemical reaction of a photoresist induced by plasmonic near-field light and propagating light in a photoresist film. This propagating light is a radiation mode from a higher order of localized surface plasmon resonances scattered by metallic nanostructures. The system does not induce nano-pattern deformation at the time of mask release. This system presents a simple alternative for producing nano-patterns instead of using nanoimprinting.
  • Zheyu Li, Kai Sun, Misato Sunayama, Ryoko Araki, Kosei Ueno, Masumi Abe, Hiroaki Misawa
    ELECTROPHORESIS 32 23 3392 - 3398 2011年11月 [査読有り][通常論文]
     
    Fraction collection of selected components from a complex mixture plays a critical role in biomedical research, environmental analysis, and biotechnology. Here, we introduce a novel electrophoretic chip device based on a signal processing theorem that allows simultaneous space sampling for fractionation of ssDNA target fragments. Ten parallel extraction channels, which covered 1.5-mm-long sampling ranges, were used to facilitate the capturing of fast-moving fragments. Furthermore, the space sampling extraction made it possible to acquire pure collection, even from partly overlapping fragments that had been insufficiently separated after a short electrophoretic run. Fragments of 180, 181, and 182 bases were simultaneously collected, and then the recovered DNA was PCR amplified and assessed by CE analysis. The 181-base target was shown to be isolated in a 70-mm-long separation length within 10?min, in contrast to the >50?min required for the 300-mm-long separation channel in our previous study. This method provides effective combination of time and space, which is a breakthrough in the traditional concept of fraction collection on a chip.
  • S. Danworaphong, T. A. Kelf, O. Matsuda, M. Tomoda, Y. Tanaka, N. Nishiguchi, O. B. Wright, Y. Nishijima, K. Ueno, S. Juodkazis, H. Misawa
    APPLIED PHYSICS LETTERS 99 20 201910  2011年11月 [査読有り][通常論文]
     
    We image gigahertz surface acoustic waves normally incident on a microscopic linear array of triangular holes-a generic "acoustic diode" geometry-with a real-time ultrafast optical technique. Spatiotemporal Fourier transforms reveal wave diffraction orders in k-space. Squared amplitude reflection and transmission coefficients for incidence on both sides of the array are evaluated and compared with numerical simulations. We thereby directly demonstrate acoustic rectification with an asymmetric structure. (C) 2011 American Institute of Physics. [doi:10.1063/1.3662930]
  • Yosuke Harada, Kohei Imura, Hiromi Okamoto, Yoshiaki Nishijima, Kosei Ueno, Hiroaki Misawa
    JOURNAL OF APPLIED PHYSICS 110 10 104306  2011年11月 [査読有り][通常論文]
     
    Modification of photovoltaic devices with metallic nanoparticles is expected to be one of the key methods for development of high performance devices as a future energy source. To clarify the mechanism of photocurrent changes induced by surface plasmon resonances of metal nanoparticles, we measured near-field photocurrent excitation images for a GaAs photodiode modified with gold nanospheres (diameter 100 nm) with a spatial resolution higher than 100 nm. The relationship between the photovoltaic efficiency and the plasmons of the gold nanospheres was investigated through the measurements of incident wavelength and polarization dependence of the near-field photocurrent images. Isolated nanospheres deposited on the GaAs active surface caused local photocurrent suppressions at the plasmon resonance wavelengths. In the case of assemblies (dimers and trimers) of the spheres, a remarkable decrease of photocurrent at the gap site between the spheres was observed. From the results, it turned out that the enhanced optical fields created via the plasmons on the metal nanostructures do not improve the photovoltaic efficiency and that forward scattering of photons by the gold nanoparticles is considered to be more important than the enhanced field effect at the particles for the GaAs photovoltaic device studied. (C) 2011 American Institute of Physics. [doi:10.1063/1.3662114]
  • L. Wang, W. Xiong, Y. Nishijima, Y. Yokota, K. Ueno, H. Misawa, J. R. Qiu, G. Bi
    Appl. Opt. 50 28 5600  2011年10月 [査読有り][通常論文]
  • Li Wang, Wei Xiong, Yoshiaki Nishijima, Yukie Yokota, Kosei Ueno, Hiroaki Misawa, Jianrong Qiu, Gang Bi
    APPLIED OPTICS 50 28 5600 - 5605 2011年10月 [査読有り][通常論文]
     
    Ag/Au bimetallic nanoparticles possess the combinatory advantages of Au and Ag nanoparticles and can also be utilized to tune the properties of localized surface plasmon resonance. Ag/Au bilayer nanorods were prepared by electron beam lithography, and their spectral properties were investigated. Compared with Ag monolayer nanorods, Ag/Au bilayer nanorods show broader localized surface plasmon resonance bands, and the longitudinal mode and transverse mode localized surface plasmon bands show blueshift and redshift, respectively. The maximum near-field intensity of the longitudinal mode of the Ag/Au nanorod is less than half that of the Ag/Au nanorod without gold layer. Shape-induced modification of Ag/Au bilayer nanorods on their spectral properties was also discussed. (C) 2011 Optical Society of America
  • A. Kolloch, T. Geldhauser, K. Ueno, H. Misawa, J. Boneberg, A. Plech, P. Leiderer
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 104 3 793 - 799 2011年09月 [査読有り][通常論文]
     
    We report on recent insights into the interaction between ultra-fast laser pulses and plasmonic nanoparticles. We discuss femtosecond near-field ablation as a simple but versatile tool for the nanoscale modification of surfaces and the high-resolution measurement of a nanostructure's near field. Two model systems are presented, illustrating the complexity of near-field distributions. Furthermore, finite difference time domain calculations in combination with absorption spectra provide a deeper insight into the factors influencing the near-field distribution. For the first time, an almost perfect agreement between the measured ablation pattern and experiment has been reached for gold triangles with a side length around 500 nm. Additionally, the results from picosecond laser irradiated plasmonic structures display a new regime of nanoscale laser material processing. We present first results showing nanometre confined melting induced by laser pulses.
  • E. Wu, Yingzhi Chi, Botao Wu, Kangwei Xia, Yukie Yokota, Kosei Ueno, Hiroaki Misawa, Heping Zeng
    JOURNAL OF LUMINESCENCE 131 9 1971 - 1974 2011年09月 [査読有り][通常論文]
     
    Metallic bowtie nanostructures as plasmonic nanoantennas can create highly enhanced local fields when resonating with the incident light. With Au bowtie nanostructures fabricated by lithography method, we experimentally observed that the photoluminescence (PL) spatial profile from a single Au bowtie nanoantenna was strongly dependent on the excitation light polarization. While varying the incident light polarization, the spatial distribution of the PL intensity in the nanogap of an Au bowtie changed as predicted by the simulation results on the electromagnetic field enhancement distribution. The polarization feature of the PL intensity relative to the polarization direction of incident excitation light was also discussed. The study may find application in the design of polarization sensitive plasmonic sensors. (C) 2011 Elsevier B.V. All rights reserved.
  • Li Wang, Wei Xiong, Yoshiaki Nishijima, Yukie Yokota, Kosei Ueno, Hiroaki Misawa, Gang Bi, Jianrong Qiu
    IEEE PHOTONICS TECHNOLOGY LETTERS 23 17 1216 - 1218 2011年09月 [査読有り][通常論文]
     
    Plasmonic spectral properties of silver nanoblocks fabricated by electron beam lithography are investigated. The extinction spectra of silver nanoblocks showed a red shift, broadening, and damping with the passage of storage time. In contrast, silver nanoblocks with titanium coating on the top did not show apparent spectral change even after storage for two months. Morphological change of the silver nanoblocks was characterized by scanning electron microscope. The present work clearly demonstrates that coating titanium on the top of the silver nanostructures is an effective way to prevent them from chemical corrosion and stabilize their plasmonic spectral properties.
  • Yutaka Yoshida, Seiichi Watanabe, Yoshiaki Nishijima, Kosei Ueno, Hiroaki Misawa, Takahiko Kato
    NANOTECHNOLOGY 22 37 375607-1-7  2011年09月 [査読有り][通常論文]
     
    A gold/silicon nanocomposite structure (NCS) was formed on a Si(100) surface by nanosecond pulsed laser irradiation. The Au/Si NCS contained both Au nanoparticles (NPs) and Au-Si alloy layers. We report that the use of laser irradiation to form Au NPs comprises two competing processes: a top-down effect involving decomposition into smaller NPs and a bottom-up effect involving self-assembly or self-organization into larger NPs. The formation of the periodic structure involved self-organization, i.e., the bottom-up effect, and was observed in situ using a pulsed-laser-equipped high-voltage electron microscope. The NCS formed by laser irradiation can be controlled by adjusting the laser energy density and the number of laser pulses.
  • Kita, Shota, Hachuda, Shoji, Otsuka, Shota, Endo, Tatsuro, Imai, Yasunori, Nishijima, Yoshiaki, Misawa, Hiroaki, Baba, Toshihiko
    OPTICS EXPRESS 19 18 17683 - 17690 2011年08月 [査読有り][通常論文]
     
    Microphotonic sensors have been actively studied with increasing demands for label-free biosensing in medical diagnoses and life sciences. For high-throughput and low-cost sensing, a high sensitivity is crucial for eliminating the pre-concentration process, while a simple setup of sensors is also desirable. This paper demonstrates a super-sensitivity for protein, which satisfies these requirements. The key device is a photonic crystal nanolaser, in particular with a nanoslot. Even using a simple setup, the nanolaser achieves an extraordinary-low detection limit for BSA protein, i.e. 255 fM on an average, which cannot be explained by its bulk index sensitivity. The specific adsorption of the protein is observed only around the nanoslot with strong laser intensity. This suggests that the super-sensitivity arises from the effective trapping of protein in the nanoslot. (C) 2011 Optical Society of America
  • Kosei Ueno, Satoaki Takabatake, Ko Onishi, Hiroko Itoh, Yoshiaki Nishijima, Hiroaki Misawa
    APPLIED PHYSICS LETTERS 99 1 011107  2011年07月 [査読有り][通常論文]
     
    We report an innovative lithography system appropriate for fabricating sharp-edged nanodot patterns with nanoscale accuracy using plasmon-assisted photolithography. The key technology is two-photon photochemical reactions of a photoresist induced by plasmonic near-field light and the scattering component of the light in a photoresist film. The scattering component of the light is a radiation mode from higher order localized surface plasmon resonances scattered by metallic nanostructures. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3606505]
  • Kosei Ueno, Hiroaki Misawa
    Journal of Photochemistry and Photobiology A: Chemistry 221 2-3 130 - 137 2011年06月25日 [査読有り][通常論文]
     
    To achieve a future low-carbon society, the effective utilization of photons is essential for the development of technologies based on photochemistry, such as photocatalysis and dye-sensitized solar cells, which have the potential to produce clean energy as well as preserve the environment. Here, we propose that gold nanostructures exhibiting localized surface plasmon (LSP) resonance are promising sites for photochemical reaction fields that increase the interaction between a photon and molecule. These interactions are based on electromagnetic field enhancement effects that are induced by LSP excitations and their localization. In this review, recent studies on the strong coupling field between a photon and molecule for photochemical reactions are discussed. As an outstanding example, this concept was applied to the plasmonic, photoelectric conversion of visible to near-infrared wavelengths using electrodes in which gold nanoblocks were elaborately arrayed on the surface of a single TiO2 crystal. The most important characteristic of this photoelectric conversion is that the photocurrent was stable for more than 200 h without adding the donors, which suggests the possibility that water molecules can act as donors that provide electrons to the d-band holes assisted by the LSP excitation. Therefore, this system has the potential for use in artificial photosynthesis systems with irradiation from near-infrared light. © 2011 Elsevier B.V. All rights reserved.
  • Hiroaki Misawa
    Journal of Photochemistry and Photobiology A: Chemistry 221 2-3 129  2011年06月25日 [査読有り][通常論文]
  • Kosei Ueno, Hiroaki Misawa
    JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 221 2-3 130 - 137 2011年06月 [査読有り][通常論文]
     
    To achieve a future low-carbon society, the effective utilization of photons is essential for the development of technologies based on photochemistry, such as photocatalysis and dye-sensitized solar cells, which have the potential to produce clean energy as well as preserve the environment. Here, we propose that gold nanostructures exhibiting localized surface plasmon (LSP) resonance are promising sites for photochemical reaction fields that increase the interaction between a photon and molecule. These interactions are based on electromagnetic field enhancement effects that are induced by LSP excitations and their localization. In this review, recent studies on the strong coupling field between a photon and molecule for photochemical reactions are discussed. As an outstanding example, this concept was applied to the plasmonic, photoelectric conversion of visible to near-infrared wavelengths using electrodes in which gold nanoblocks were elaborately arrayed on the surface of a single TiO2 crystal. The most important characteristic of this photoelectric conversion is that the photocurrent was stable for more than 200 h without adding the donors, which suggests the possibility that water molecules can act as donors that provide electrons to the d-band holes assisted by the LSP excitation. Therefore, this system has the potential for use in artificial photosynthesis systems with irradiation from near-infrared light. (C) 2011 Elsevier B.V. All rights reserved.
  • Tobias Geldhauser, Shintarou Ikegaya, Andreas Kolloch, Naoki Murazawa, Kosei Ueno, Johannes Boneberg, Paul Leiderer, Elke Scheer, Hiroaki Misawa
    PLASMONICS 6 2 207 - 212 2011年06月 [査読有り][通常論文]
     
    We report in this paper the near-field distribution in the case of gold triangle arrays by means of two-photon polymerization for a dipole and a quadrupole plasmon mode. In order to link the finite difference in the time domain (FDTD) simulations of the triangle array and the experimental results, extinction spectra for both cases in air and SU-8 environments are shown. In case of the 40-nm thick gold triangles with 85-nm side-length, we show that the calculated and experimentally obtained near-field for the excited dipole mode has the same distribution along the polarization of the exciting laser beam. In case of bigger triangles of 540-nm side-length a quadrupole mode is excited, which leads to a rotation of the near-field distribution by 90A degrees referred to the polarization of the beam. This effect is also shown in the FDTD simulations.
  • Li Wang, Yoshiaki Nishijima, Kosei Ueno, Hiroaki Misawa, Naoto Tamai
    JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 221 2-3 164 - 168 2011年06月 [査読有り][通常論文]
     
    Gold pair nanocuboids (size: 150 nm x 150 nm x 20 nm) with different nanogaps ranging from 0 to 10.6 nm were prepared by the electron-beam lithography. Effect of plasmon coupling on coherent acoustic phonon dynamics of gold pair nanocuboids was examined as a function of nanogaps by near-IR transient absorption spectroscopy at 400-nm excitation. The similar oscillation periods of coherent acoustic phonon vibration (88 +/- 1 ps) were observed for all the gold pair nanocubiods irrespective of the nanogaps, which was analyzed by the oscillation of bleaching peaks of SPR bands and the transient absorption dynamics. The coherent acoustic phonon vibration of gold nanocuboids was only influenced by the nanostructure itself, even though SPR band was much influenced due to the dipole coupling between the adjacent Au nanocuboids. In addition, it was revealed that the electron-phonon coupling (similar to 0.7 ps) was followed by the initial size change of gold nanocuboid with the time scale that was a little slower (similar to 1.7 ps) than the electron-phonon coupling. (C) 2011 Elsevier B.V. All rights reserved.
  • Susumu Haruta, Hiroaki Misawa, Kosei Ueno, Yukie Yokota, Hiroki Uehara, Hiroshi Hiratsuka, Hiroaki Horiuchi, Tetsuo Okutsu
    JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 221 2-3 268 - 272 2011年06月 [査読有り][通常論文]
     
    Photochemically induced protein crystallization byprotein's multiphoton excitation based on enhanced field of localized surface plasmon resonance (LSPR) of gold nanostructures was investigated. As strong photons-molecules coupling fields, gold nanostructures composed of nanoblocks and gold nanocolloid were used. With gold nanostructures, we could observe enzyme activity decrease by light irradiation that protein does not absorb. Surface observation of gold nanostructure by DFM (non-contact dynamic force microscope) shows that proteins were aggregated at around the nanoblock due to photochemical reaction by enhanced field. Crystallization probability depends on the excitation photon fluence, which indicates 3 photons absorption process occurred. (C) 2011 Elsevier B.V. All rights reserved.
  • S. Gao, K. Ueno, and H. Misawa
    Plasmonic Antenna, Effects on, Photochemical Reactions
    Accounts of chemical research 44 4 251 - 260 2011年05月 [査読有り][通常論文]
  • Li Wang, Wei Xiong, Yoshiaki Nishijima, Yukie Yokota, Kosei Ueno, Hiroaki Misawa, Gang Bi, Jian-rong Qiu
    OPTICS EXPRESS 19 11 10640 - 10646 2011年05月 [査読有り][通常論文]
     
    The instability of silver nanoblocks under atmospheric conditions is investigated. The localized surface plasmon resonance band of the silver nanoblocks shows a red shift, broadening, and damping with increasing storage time under atmospheric conditions. The change in spectral properties of silver nanoblocks is considered to be due to sulfidation of silver and structural breakage of silver nanoblock based on scanning electron microscope observation and numerical simulation. The effect of aspect ratio of silver nanoblocks on the change in spectral properties of the nanoengineered silver blocks is also discussed. (C) 2011 Optical Society of America
  • Yoshito Tanaka, Hiroyasu Ishiguro, Hideki Fujiwara, Yukie Yokota, Kosei Ueno, Hiroaki Misawa, Keiji Sasaki
    OPTICS EXPRESS 19 8 7726 - 7733 2011年04月 [査読有り][通常論文]
     
    We perform direct local-field imaging of a plasmon-resonant gold nanoparticle pair separated by a gap of several nanometers using a scattering-type near-field optical microscope with a sharp silicon tip of atomic force microscope. The sharp tip allows the access for the nanogap and the high spatial resolution. Our results provide experimental evidence that the nanogap structure produces an optical spot with the size of a single nanometer (< 10 nm). This is not only of fundamental importance in the field of nanophotonics, but also provide significant information for the development of plasmonic devices with the nanogap structures. (C) 2011 Optical Society of America
  • Kohei Imura, Kosei Ueno, Hiroaki Misawa, Hiromi Okamoto
    Nano Letters 11 3 960 - 965 2011年03月09日 [査読有り][通常論文]
     
    We report an anomalous light transmission phenomenon for a nanoaperture on an opaque screen when the aperture is covered with an opaque cap. In conventional optics, light transmission must decrease when the aperture is capped. However, we found that light transmission is enhanced when the nanodisk is in close proximity to the aperture at a wavelength close to the plasmon resonance. This effect even occurs when the disk is larger than the aperture. © 2011 American Chemical Society.
  • Kohei Imura, Kosei Ueno, Hiroaki Misawa, Hiromi Okamoto
    NANO LETTERS 11 3 960 - 965 2011年03月 [査読有り][通常論文]
     
    We report an anomalous light transmission phenomenon for a nanoaperture on an opaque screen when the aperture is covered with an opaque cap. In conventional optics, light transmission must decrease when the aperture is capped. However, we found that light transmission is enhanced when the nanodisk is in close proximity to the aperture at a wavelength dose to the plasmon resonance. This effect even occurs when the disk is larger than the aperture.
  • Zheyu Li, Kai Sun, Misato Sunayama, Yasutaka Matsuo, Vygantas Mizeikis, Ryoko Araki, Kosei Ueno, Masumi Abe, Hiroaki Misawa
    JOURNAL OF CHROMATOGRAPHY A 1218 7 997 - 1003 2011年02月 [査読有り][通常論文]
     
    High efficiency and high-purity fraction collection is highly sought in analysis of fragments-of-interest from selective polymerase chain reaction (PCR) products generated by High Coverage Gene Expression Profiling (HiCEP) methods. Here we demonstrate a new electrophoretic chip device enabling automatic high-efficient fractionation of multiple ssDNA target fragments during a run of separation. We used thoroughly isolated extraction channels for each selected target to reduce the risk of cross-contamination between targets due to cross-talk of extraction channels. Fragments of 35, 108 and 138 b, were successfully isolated, then the recovery was PCR-amplified and assessed by capillary electrophoresis (CE) analysis. Total impurity level of the targets due to unwanted fragments of 0.7%, 2% and 6% respectively, was estimated. Difficulties in collecting multiple target factions are due to band diffusion and DNA adsorption to the walls for the fragments in the separation channel, which is generated by transferring the DNA target fraction from the extraction section to the target reservoir. Therefore, we have carefully measured band broadening and analyzed its influence on the separation resolution due to the delay. (C) 2010 Elsevier B.V. All rights reserved.
  • Fuyuki Ito, Ryuichi Ohta, Yukie Yokota, Kosei Ueno, Hiroaki Misawa, Toshihiko Nagamura
    MOLECULAR CRYSTALS AND LIQUID CRYSTALS 538 265 - 271 2011年 [査読有り][通常論文]
     
    The polarization dependence of excitation light for fluorescence enhancement of near-infrared dyes immobilized in hydrophobic DNA thin film on glass substrates with regularly arranged Au nanoblocks was investigated. The enhancement factor for S-polarized excitation was about 1.2 to 1.5 times as large as that for P-polarized excitation. P-polarized light contributed to the excitation of plasmon band both of horizontal and vertical direction of Au nanoblocks. The vertical direction corresponds to the short axis for height direction which has the absorption in visible region did not contribute the excitation of IR780. When the absorption band of Au array and the fluorescence band of IR780 were overlapped, the fluorescence enhancement did not depend on the polarization of excitation light. It is suggested that the fluorescence quenching originates from the energy transfer from the excited state of IR780 to Au nanoblocks or the increased deactivation of excited dye molecules induced by resonance with Au nanoblocks.
  • Yukie Yokota, Kosei Ueno, Hiroaki Misawa
    SMALL 7 2 252 - 258 2011年01月 [査読有り][通常論文]
     
    Well defined gold nanostructures of various sizes are fabricated on glass substrates using high-resolution electron-beam lithography/lift-off techniques and detailed surface-enhanced Raman scattering (SERS) properties of crystal violet molecules are studied in order to elucidate electromagnetic (EM) field enhancement effects on the fabricated structures. SERS measurements are performed with high reproducibility using in situ Raman microspectroscopy in aqueous solution. An analysis based on EM theory is performed using field-enhancement factors obtained from finite-difference time-domain (FDTD) simulations and the analysis reproduces experimental results very well. It is noteworthy, furthermore, that the proposed analytic method of EM effects on SERS allows the estimate of the ideal local temperature of gold nanostructures by canceling out the difference in EM field factors at Stokes and anti-Stokes Raman scattering wavelengths. Thus, these experimental results demonstrate that quantitative analysis based on EM theory can be obtained using highly controlled gold nanostructures for SERS measurements with high reproducibility, a result that is promising for the construction of a SERS analysis chip. Although no SERS chip reported so far has been usable for quantitative analysis, this study opens the door for construction of a quantitative SERS chip.
  • Yukie Yokota, Kosei Ueno, Hiroaki Misawa
    CHEMICAL COMMUNICATIONS 47 12 3505 - 3507 2011年 [査読有り][通常論文]
     
    We have demonstrated the essential nanogap effects on surface-enhanced Raman scattering (SERS) signals obtained from two diagonally aligned gold nanoparticles with several nanometre separations, which were precisely fabricated on a glass substrate. This is the first proof of principle for extracting the light localization effects on SERS due to the formation of nanogaps from experimentally observed SERS signals.
  • Ya-Wei Hao, Hai-Yu Wang, Ying Jiang, Qi-Dai Chen, Kosei Ueno, Wen-Quan Wang, Hiroaki Misawa, Hong-Bo Sun
    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 50 34 7824 - 7828 2011年 [査読有り][通常論文]
  • Plasmon-Enhanced Water Oxidation on Gold Nanostructured TiO2 Single Crystal Substrates
    Misawa Hiroaki, Nishijima Yoshiaki, Ueno Kosei, Murakoshi Kei, Inoue Haruo
    Meeting Abstracts 36 1295  2011年 [査読有り][通常論文]
  • Trapping of protein in nanoslot nanolaser sensor
    Shota Kita, Shota Otsuka, Tatsuro Endo, Yoshiaki Nishijima, Hiroaki Misawa, Toshihiko Baba
    15th International Conference on Miniaturized Systems for Chemistry and Life Sciences 2011, MicroTAS 2011 2 3 1275-1277  2011年 [査読有り][通常論文]
  • Controlling plasmonic spectral properties of engineered silver nanorods by using titanium coating
    Wang Li, Xiong Wei, Nishijima Y, Yokota Y, Ueno K, Misawa H, Bi G, Qiu JR
    IEEE Photon. Technol. Lett. 2011年 [査読有り][通常論文]
  • Fuyuki Ito, Ryuichi Ohta, Yukie Yokota, Kosei Ueno, Hiroaki Misawa, Toshihiko Nagamura
    CHEMISTRY LETTERS 39 11 1218 - 1219 2010年11月 [査読有り][通常論文]
     
    Fluorescence intensity of near Infrared dyes immobilized in hydrophobic DNA thin film spin-coated on glass substrates with regularly arranged gold (Au) nanoblocks was about 2 5 times larger than that without Au nanoblocks, strongly suggesting the fluorescence intensity was enhanced by increased electric field intensity of excitation light due to local plasmon resonance of Au nanoblocks
  • Quan Sun, Hidenori Asahi, Yoshiaki Nishijima, Naoki Murazawa, Kosei Ueno, Hiroaki Misawa
    OPTICS EXPRESS 18 24 24495 - 24503 2010年11月 [査読有り][通常論文]
     
    The nonlinear propagation of a single focused femtosecond laser pulse in fused silica has been investigated both experimentally and by numerical simulations. In particular, the filamentation behavior was systematically studied by varying pulse duration. At low pulse energy, the peak plasma density inside the filament first increases to a maximum value with increasing pulse duration and then begins to decrease. At relatively high pulse energy, denser plasma can be induced around the geometrical focus with a certain longer pulse duration, where the peak power is already below the self-focusing critical power and no filament is formed. This pulse duration dependent behavior can be explained by different ionization mechanisms. (c) 2010 Optical Society of America
  • Bin-Bin Xu, Hong Xia, Li-Gang Niu, Yong-Lai Zhang, Kai Sun, Qi-Dai Chen, Ying Xu, Zhi-Qiu Lv, Zhi-Hong Li, Hiroaki Misawa, Hong-Bo Sun
    SMALL 6 16 1762 - 1766 2010年08月 [査読有り][通常論文]
  • Yoshiaki Nishijima, Kosei Ueno, Yukie Yokota, Kei Murakoshi, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY LETTERS 1 13 2031 - 2036 2010年07月 [査読有り][通常論文]
     
    Nanoparticles of noble metals exhibit localized surface plasmons (LSPs) associated with the enhancement of an electromagnetic field due to its localization in nanometric domains at the surface of nanoparticles. We demonstrate the plasmonic photoelectric conversion from visible to near-infrared wavelength without deteriorating photoelectric conversion by using electrodes in which gold nanorods are elaborately arrayed on the surface of a TiO2 single crystal.
  • Hiroyo Segawa, Kosei Ueno, Yukie Yokota, Hiroaki Misawa, Tetsuji Yano, Shuichi Shibata
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 93 6 1634 - 1638 2010年06月 [査読有り][通常論文]
     
    Nanopatterns of a TiO2-organic hybrid material have been fabricated with the use of a localized surface plasmon (LSP). The TiO2-organic hybrid material was prepared by the sol-gel method and was coated on a glass substrate with gold nanoblocks. After the hybrid films were irradiated with a femtosecond laser, the unreacted parts were removed, leaving the TiO2-organic hybrid materials around the nanoblocks. In the nanopatterns of the TiO2-organic hybrid materials, the pi - pi* transition absorption band of the chelate compound formed between Ti-alkoxide and beta-diketone was excited by the two-photon absorption induced by the LSP of gold nanoblocks, and the chelate compound was decomposed and dissolved in alcohol. It was confirmed that the hybrid material changed to anatase upon sintering above 450 degrees C.
  • Vygantas Mizeikis, Saulius Juodkazis, Kai Sun, Hiroaki Misawa
    JOURNAL OF LASER MICRO NANOENGINEERING 5 2 115 - 120 2010年06月 [査読有り][通常論文]
     
    Simple frequency-selective surface (FSS) structures consisting of two-dimensional (2D) triangular lattices of circular apertures with an aperture diameter of about 0.6-0.8 mu m and a lattice period of 1.0 and 2.0 mu m were fabricated by femtosecond laser ablation of thin gold films deposited on glass substrates. The fabricated samples were found to exhibit spectral transmission bands at infrared wavelengths, and significant surface plasmonic (SP) local enhancement of the near-field near the metal's surface according to experimental transmission measurements and theoretical simulation by Finite-Difference Time-Domain (FDTD) technique. These results indicate versatility of femtosecond laser ablation technique for rapid prototyping of metallic FSS and plasmonic structures. DOI:10.2961/jlmn.2010.02.0003
  • Kestutis Juodkazis, Jurga Juodkazyte, Putinas Kalinauskas, Titas Gertus, Edgaras Jelmakas, Hiroaki Misawa, Saulius Juodkazis
    JOURNAL OF SOLID STATE ELECTROCHEMISTRY 14 5 797 - 802 2010年05月 [査読有り][通常論文]
     
    Influence of direct laser writing with femtosecond pulses on electrochemical etching of n-type low conductivity (> 1,000 Omega cm) silicon is demonstrated. It has been shown that thermal 1-A mu m-thick SiO(2) layer on silicon surface can be used as a protective layer in the electrochemical etching process. It has been found that laser ablation changes not only the surface morphology and structure of silicon samples but also the character of their anodic etching in aqueous solution of hydrofluoric acid. Formation of microvoids and caverns of irregular shape has been observed at the laser-ablated sites. It is proposed that the change of silicon conductivity from n- to p-type takes place at the laser fabricated regions. Processes of Si anodic oxidation and electrochemical etching are discussed.
  • Takeshi Tsuji, Kosei Ueno, Yukie Yokota, Masaharu Tsuji, Hiroaki Misawa
    JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 212 1 20 - 26 2010年04月 [査読有り][通常論文]
     
    Photoinduced shape changes of metal nanostructures in halide solutions were investigated using gold and silver nanoblocks (NBs) patterned on a glass substrate, instead of nanoparticles dispersed in solution. It was found that size reduction of the NBs by halide etching was enhanced by photoirradiation. Furthermore, it was revealed that the halide etching efficiency corresponded to the intensity of the electric field induced by localized surface plasmon resonance (LSPR) of the NBs. The enhancement of halide etching by LSPR was explained on the basis of electron transfer reactions from metal NBs. Throughout this study, it was demonstrated that metal NBs fabricated on a substrate constitute a powerful system to investigate photoinduced shape changes of nanostructures, because of their defined shape, position, and configuration. (C) 2010 Elsevier B.V. All rights reserved.
  • T. Dehoux, T. A. Kelf, M. Tomoda, O. Matsuda, O. B. Wright, K. Ueno, Y. Nishijima, S. Juodkazis, H. Misawa, V. Tournat, V. E. Gusev
    Optics Letters 35 7 940  2010年04月01日 [査読有り][通常論文]
  • Quan Sun, Saulius Juodkazis, Naoki Murazawa, Vygantas Mizeikis, Hiroaki Misawa
    JOURNAL OF MICROMECHANICS AND MICROENGINEERING 20 3 035004  2010年03月 [査読有り][通常論文]
     
    We present a method to fabricate freestanding and movable photonic microstructures by photopolymerization in a zirconium-based sol-gel hybrid resist with femtosecond laser three-dimensional (3D) direct writing. The freestanding microstructures exhibit much less distortion than the conventional structures attached to substrates, especially when made at close to the photopolymerization threshold. A few percent shrinkage which exists rescales the structure and it can lead to the shift of the photonic stop band toward shorter wavelengths. Fabrication of freestanding and freely movable (in micro-fluidic environment) 3D microstructures realizes a simple approach to quantitatively study the shrinkage of photopolymers and to improve the resolution. 3D-movable micro-optical elements with designed photonic properties and micro-devices have potential in opto-fluidics and opto-micro-mechanical applications based on laser trapping and manipulation.
  • Kosei Ueno, Satoaki Takabatake, Yoshiaki Nishijima, Vygantas Mizeikis, Yukie Yokota, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY LETTERS 1 3 657 - 662 2010年02月 [査読有り][通常論文]
     
    Nanoparticles of noble metals exhibit localized surface plasmons (LSP) associated with enhancement of the electromagnetic field due to its localization in nanometric domains at the surface of nanoparticles. Especially, nanogapmetallic structures show strong enhancement of the electromagnetic field at the nanogap position. This can be achieved up to 10(5) times larger than the incident light field. We have explored the possibility to use the localized field for nanogap-assisted surface plasmon nanolithography. For the purpose, monidisperse arrays consisting of pairs of rectangular gold nanoblocks separated by nanogaps were fabricated on glass substrates using electron beam lithography and lift-off techniques. Nanoblock structures were used as photomasks for contact exposure of thinfilms of positive photoresist on glass substrates. Thus, ordered clusters of nanoparticles separated by nanogaps can provide a stable and versatile platform for further development of optical subwavelength nanolithography. To the best of our knowledge, this is the first proof-of-principle demonstration of such a technique.
  • Eugene G. Gamaly, Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa, Andrei V. Rode, Wieslaw Krolikowski
    PHYSICAL REVIEW B 81 5 054113  2010年02月 [査読有り][通常論文]
     
    We demonstrate that the interaction of intense femtosecond pulse with photorefractive crystal at conditions close to the optical-breakdown threshold differs drastically from that of long pulse and cw illumination. Our theoretical estimations show that the high number density of excited electrons modifies the dielectric function leading to the transient negative change in the refractive index, Delta n/n(0)similar to-10(-2) that vanishes on nanosecond time scale. Moreover, the high-frequency laser field, two orders of magnitude larger than the field of spontaneous polarization, prevents the stationary charge distribution during the pulse. The diffusion and recombination of charge carriers continues over a nanosecond time scale, after the end of the pulse. The main driving force for the current after the pulse is the field of spontaneous polarization in the ferroelectric medium: the current terminates when the field of charge separation balances this field. We show here that the stationary modification of refractive index according to this model is then independent of the polarization of the pump light beam, in agreement with experiments, and saturates at Delta n approximate to 10(-3) in semiquantitative fit to the experimental data.
  • Md Monirul Islam, Kosei Ueno, Saulius Juodkazis, Yukie Yokota, Hiroaki Misawa
    ANALYTICAL SCIENCES 26 1 13 - 18 2010年01月 [査読有り][通常論文]
     
    Interdigitated array electrodes with surface-enhanced Raman scattering (SERS) functionality for in situ qualitative and quantitative analysis of electroactive species are demonstrated. Gold nanostructured interdigitated array electrodes (NIDAEs) were fabricated by electron beam lithography, and used for an electrochemical SERS study of K(3)[Fe(CN(6))] in aqueous KClO(4) solution in single and generation-collection modes. The generation-collection mode experiment showed amplification of the SERS band intensity for adsorbed ferricyanide ions at the negative end of the applied potential, while in single mode it was reduced to near zero. This new finding reveals that NIDAEs offer a new opportunity for analytical science by improving analytical sensitivity and detection ability of electroactive species. The electric fields accumulating at nanogaps are promising for manipulating linear and nonlinear optical phenomena. In addition, miniaturized NIDAEs are of great importance for developing lab-on-a-chip devices, and are useful for measurements within small space/volume domains, requiring only small amounts and/or concentrations of analytes.
  • Md Monirul Islam, Kosei Ueno, Hiroaki Misawa
    ANALYTICAL SCIENCES 26 1 19 - 24 2010年01月 [査読有り][通常論文]
     
    Nanostructured interdigitated array (IDA) electrodes with different inter-electrode spacing were demonstrated to improve the detection sensitivity of short-lived electroactive species and to follow interfacial dynamics by their surface-enhanced Raman scattering (SERS) functionality. Nanostructured IDA electrodes fabricated using electron beam lithography were used for an electrochemical SERS study of irreversible electroactive species, crystal violet (CV), in an aqueous KCl solution in single and generation-collection (GC) mode experiments. The GC mode enabled us to amplify the SERS intensity. An inter-electrode spacing dependent study found the maximum number of redox cycling, collection efficiency and amplification of the SERS intensity. Its SERS function disclosed the potential-dependent dynamics of CV molecules at the electrode surface, which was not observed in the redox current. Miniaturized nanostructured IDA electrodes are of great importance for developing lab on chip devices, and are useful for analyzing dynamical features within small space/volume domains, which require small amounts and/or concentration of analytes.
  • Vygantas Mizeikis, Saulius Juodkazis, Kai Sun, Hiroaki Misawa
    ADVANCED FABRICATION TECHNOLOGIES FOR MICRO/NANO OPTICS AND PHOTONICS III 7591 2010年 [査読有り][通常論文]
     
    We report maskless microfabrication of periodic structures in thin metallic films by femtosecond laser ablation. Two-dimensional (2D) triangular arrays of circular apertures with diameter of about 0.6 - 0.8 mu m and a lattice period of 1.0 and 2.0 mu m were fabricated by single-and multiple laser pulse ablation of 35 nm thick gold films sputtered on glass substrates. Optical transmission spectra of the fabricated samples exhibit transmission bands at infrared wavelengths. Theoretical modeling of the optical properties by Finite-Difference Time-Domain (FDTD) technique indicates that these bands are associated with localized and propagating surface plasmon (SP) modes. FDTD simulations also indicate substantial resonant enhancement of the near-field intensity at the metal's surface. Laser ablation of thin metallic films is therefore a promising route for fast prototyping of planar metallic micro-and nano-structures applicable as frequency-selective surfaces (FSS) and SP substrates.
  • Quan Sun, Saulius Juodkazis, Naoki Murazawa, Vygantas Mizeikis, Hiroaki Misawa
    Proceedings of SPIE - The International Society for Optical Engineering 7591 75910K  2010年 [査読有り][通常論文]
     
    We present the fabrication of microstructures for photonic and micro-/opto-fluidic applications using femtosecond laser 3D direct writing technique in zirconium-based sol-gel hybrid resist. The advantages and mechanism of photo-polymerization of this new material under fs-pulsed laser exposure are discussed. We suggest and achieve a novel method to fabricate free-standing and movable photonic microstructures, which exhibit much less distortion than the conventional structures attached to substrates, especially when made at close to the photopolymerization threshold. Fabrication of free-movable structures allows us to quantitatively study the shrinkage of photoresist and to improve the resolution. It also contributes to tuning the stop band position of photonic crystals to shorter wavelength. Furthermore, the demonstrated freely-movable property makes it possible to laser trap and manipulate photonic microstructures and have potential application in optofluidics and bio-applications. © 2010 Copyright SPIE - The International Society for Optical Engineering.
  • Quan Sun, Hidenori Asahi, Naoki Murazawa, Kosei Ueno, Hiroaki Misawa
    2010 OSA-IEEE-COS Advances in Optoelectronics and Micro/Nano-Optics, AOM 2010 2010年 [査読無し][通常論文]
     
    We present the fabrication of photonic microstructures using femtosecond laser direct writing technique in resist. The effect of drying process on photo-polymerized microstructures is investigated. We find that shrinkage mostly arises during the drying process.
  • Shota Kita, Shoji Hachuda, Toshihiko Baba, Tatsuro Endo, Yoshiaki Nishijima, Hiroaki Misawa
    Proceedings of IEEE Sensors 2303 - 2306 2010年 [査読有り][通常論文]
     
    We have developed photonic crystal nanolaser and applied it to sensing liquids and bio-molecules. In this study, a nano-slot structure is introduced into the nanolaser, which strengthens the mode localization and improves the sensitivity, stability, and resolution as a sensor. As a result, a very low detection limit of 5.1 pg/ml has been achieved for BSA protein. It will be applicable to high-throughput label-free biosensing, while a mechanism of such low detection limit with the nano-slot is of great interest to investigate. ©2010 IEEE.
  • T. Dehoux, T. A. Kelf, M. Tomoda, O. Matsuda, O. B. Wright, K. Ueno, Y. Nishijima, S. Juodkazis, H. Misawa, V. Tournat, V. E. Gusev
    OPTICS LETTERS 34 23 3740 - 3742 2009年12月 [査読有り][通常論文]
     
    We use ultrashort optical pulses to excite and detect vibrations of single silica spheres with a diameter of 5 mu m placed at the surface of an acoustically mismatched substrate. In addition to the photoelastic detection of picosecond longitudinal acoustic pulses propagating inside the bulk, we detect gigahertz acoustic resonances of the sphere through probe beam defocusing. The mode frequencies are in close accord with those calculated from the elastic vibrations of a free sphere. We also record a resonant enhancement in the amplitude of specific modes of two touching spheres. (C) 2009 Optical Society of America
  • Kai Sun, Nobuko Suzuki, Zheyu Li, Ryoko Araki, Kosei Ueno, Saulius Juodkazis, Masumi Abe, Sumihare Noji, Hiroaki Misawa
    ELECTROPHORESIS 30 24 4277 - 4284 2009年12月 [査読有り][通常論文]
     
    For the fractionation of fragments of interest from selective PCR products generated by high coverage gene expression profiling (HiCEP) analysis, high-resolution with the ability to discriminate and fractionate fragments differing by one base (base pair) in size is highly required. We report here on a new 4-inch diameter spiral-channel chip device for automatic high-fidelity fractionation. Overlapping DNA fragments of 180, 181 and 182 bases, with only one-base difference in size, were successfully fractionated. The collected fragments were PCR amplified, and then evaluated by size checking analysis, DNA sequencing, and homolog search. The high-resolution fractionation has been achieved because of the combined contributions of (i) the high-resolution separation using a 30 cm long spiral channel, (ii) a blocking technique to avoid contamination from unselected fragments during CE, and (iii) precise micro-scale target extraction. Contaminations due to unselected fractions have been greatly decreased to a negligible level by optimization of the extraction position and extraction time corresponding to the targeted segment only. This technique can be adapted to a wide range of applications, such as protein or cell collections where requirements for the high purity are more important than the amount of recovered fractionated material.
  • Etienne Brasselet, Naoki Murazawa, Hiroaki Misawa, Saulius Juodkazis
    PHYSICAL REVIEW LETTERS 103 10 103903  2009年09月 [査読有り][通常論文]
     
    We report on the generation of mono- and polychromatic optical phase singularities from micron-sized birefringent droplets. This is done experimentally by using liquid crystal droplets whose three dimensional architecture of the optical axis is controlled within the bulk by surfactant agents. Because of its microscopic size these optical vortex generators are optically trapped and manipulated at will, thus realizing a robust self-aligned micro-optical device for orbital angular momentum conversion. Experimental observations are supported by a simple model of optical spin-orbit coupling in uniaxial dielectrics that emphasizes the prominent role of the transverse optical anisotropy with respect to the beam propagation direction.
  • Yukie Yokota, Kosei Ueno, Saulius Juodkazis, Vygantas Mizeikis, Naoki Murazawa, Hiroaki Misawa, Haruya Kasa, Kenji Kintaka, Junji Nishii
    JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 207 1 126 - 134 2009年09月 [査読有り][通常論文]
     
    This work describes fabrication of three-dimensionally nano-textured silicon surface structures metalized by thin gold films,and their application for optical sensing and detection of solute molecules utilizing surface-enhanced Raman scattering (SERS) effect. Two types of sensitive surfaces were prepared by different techniques. The first of them was a checkerboard pattern of 3D nanoblocks defined in compact areas on the surface of a silicon wafer using highly accurate electron-beam lithography (EBL) technique, and fabricated by dry reactive-ion etching (RIE) technique with subsequent metalization of the surface by gold sputtering. The second type of sensitive surface consisted of a square array of nano-apertures. defined on a large area of the silicon surface by a less accurate but simpler ultraviolet holographic lithography, and subsequently fabricated in a sequence of dry and wet etching as well as gold sputtering steps. The fabricated structures were found to exhibit significant near-field enhancement, as evidenced by strong SERS signal from the sensors immersed in aqueous pyridine solutions with concentrations as low as 10(-9) M due to the presence of well-defined 3D periodic texture of the structure. (C) 2008 Elsevier BY. All rights reserved.
  • Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa
    JOURNAL OF APPLIED PHYSICS 106 5 051101  2009年09月 [査読有り][通常論文]
     
    Femtosecond laser fabrication of three-dimensional structures for photonics applications is reviewed. Fabrication of photonic crystal structures by direct laser writing and holographic recording by multiple beam interference techniques are discussed. The physical mechanisms associated with structure formation and postfabrication are described. The advantages and limitations of various femtosecond laser microfabrication techniques for the preparation of photonic crystals and elements of microelectromechanical and micro-optofluidic systems are discussed.
  • Vygantas Mizeikis, Saulius Juodkazis, Tadas Balciunas, Sergey I. Kudryashov, Vladimir D. Zvorykin, Andrei A. Ionin, Hiroaki Misawa
    APPLIED SURFACE SCIENCE 255 24 9721 - 9723 2009年09月 [査読有り][通常論文]
     
    Millimeter-long filaments and accompanying luminous plasma and defect channels created in fused silica (FS) by single focused femtosecond laser pulses with supercritical powers were probed in situ using optical imaging and contact ultrasonic techniques. Above the threshold pulse energy E(opt) = 5 mu J corresponding to a few megawatt power levels pulses collapse due to self-focusing, producing channels filled by electron-hole plasma and luminescent defects, and exhibits predominantly compressive pressure transients. Analysis of the optical and ultrasonic response versus the laser pulse energy suggests that filamentary pulse propagation in the channels occurs with considerable dissipation of about similar to 10 cm (1). The predominant ionization mechanism is most likely associated with avalanche ionization, while the main mechanism of optical absorption is free-carrier absorption via inverse Bremsstrahlung interaction with the polar lattice. (C) 2009 Elsevier B.V. All rights reserved.
  • Vygantas Mizeikis, Shigeru Kimura, Nikolay V. Surovtsev, Vygandas Jarutis, Akira Saito, Hiroaki Misawa, Saulius Juodkazis
    APPLIED SURFACE SCIENCE 255 24 9745 - 9749 2009年09月 [査読有り][通常論文]
     
    We report on structural characterization of void-structures created by a micro-explosion at the locus of a tightly focused femtosecond laser pulse inside the crystalline phase of Al(2)O(3) (R3c space group). The transmission electron microscopy (TEM), micro-X-ray diffraction (XRD) analysis, and Raman scattering revealed a presence of strongly structurally modified amorphous regions around the void-structures. We discuss issues of achieving the required resolution for structural characterization and assignment of newly formed phases of nano-crystallites by TEM, XRD, and Raman scattering from micro-volumes of modified materials enclosed inside the bulk of the host phase. (C) 2009 Elsevier B.V. All rights reserved.
  • Li Wang, Yoshiaki Nishijima, Kosei Ueno, Hiroaki Misawa, Naoto Tamai
    APPLIED PHYSICS LETTERS 95 5 053116  2009年08月 [査読有り][通常論文]
     
    We examined vibrational dynamics of periodic gold single and pair nanocuboids with 9 nm separation at 400 nm excitation by near-IR transient absorption spectroscopy. The similar oscillation periods of coherent phonon vibration (77 +/- 1 ps) were observed for both nanocuboids while the damping of the pair was faster than that of the single. From the analysis of bleaching peak shift and finite-difference time-domain calculation, the lattice change in coherent phonon vibration was estimated to be +/- 1% for a quasiextensional and +/- 3% for an quasibreathing modes of a single nanocuboid.
  • Saulius Juodkazis, Yasufumi Nishi, Hiroaki Misawa, Vygantas Mizeikis, Olivier Schecker, Reimar Waitz, Paul Leiderer, Elke Scheer
    OPTICS EXPRESS 17 17 15308 - 15317 2009年08月 [査読有り][通常論文]
     
    The optical linear and nonlinear properties of similar to 340-nm-thick Si membranes were investigated. The investigation included both experiments in which the reflection and transmission from the membranes were measured, and finite differences time domain simulations. The linear optical transmission of the Si membranes can be controlled by changing the thickness of a thermally grown oxide on the membrane. Illumination of the membranes with high levels of irradiation leads to optical modifications that are consistent with the formation of amorphous silicon and dielectric breakdown. When irradiated under conditions where dielectric breakdown occurs, the membranes can be ablated in a well-controlled manner. Laser micro-structuring of the membranes by ablation was carried out to make micrometer-sized holes by focused fs-pulses. Ns-pulses were also used to fabricate arrays of holes by proximity-ablation of a closely-packed pattern of colloidal particles. (C) 2009 Optical Society of America
  • Paul F. Barbara, Johan Hofkens, Hiroaki Misawa, Kei Murakoshi, Tsuyoshi Asahi, Hiroshi Miyasaka
    Journal of Physical Chemistry C 113 27 11425 - 11427 2009年07月09日 [査読有り][通常論文]
  • Saulius Juodkazis, Hiroaki Misawa, Eugene G. Gamaly, Barry Luther-Davies, Ludovic Hallo, Philippe Nicolai, Vladimir T. Tikhonchuk
    JOURNAL OF NON-CRYSTALLINE SOLIDS 355 18-21 1160 - 1162 2009年07月 [査読有り][通常論文]
     
    It is demonstrated that the processes leading to nano-void formation under single-pulse tight focusing in dielectrics are described by the same laws used to describe macroscopic explosions but with energies 10(21) times lower and space and time scales reduced by 10(7). (C) 2009 Elsevier B.V. All rights reserved.
  • Kosei Ueno, Saulius Juodkazis, Toshiyuki Shibuya, Vygantas Mizeikis, Yukie Yokota, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY C 113 27 11720 - 11724 2009年07月 [査読有り][通常論文]
     
    Photopolymerization of commercial photoresist SU-8 assisted by plasmonic near-field enhancement in nanogaps separating gold nanoblocks was investigated. Photopolymerization rates enhanced by orders of magnitude were found in gold nanoblock structures with nanogaps narrower than 10 nm. The mechanisms responsible for local and nonlocal nonlinear photopolymerization of SU-8 are discussed.
  • Vygantas Mizeikis, Saulius Juodkazis, Tadas Balciunas, Hiroaki Misawa, Sergey I. Kudryashov, Vladimir D. Zvorykin, Andrei A. Ionin
    JOURNAL OF APPLIED PHYSICS 105 12 123106  2009年06月 [査読有り][通常論文]
     
    Millimeter-long filaments and accompanying luminous plasma and defect channels created in fused silica by single, moderately focused femtosecond laser pulses with supercritical powers were probed in situ using optical imaging and contact ultrasonic techniques. Above the threshold pulse energy E-opt = 5 mu J corresponding to a few megawatt power, the pulses collapse due to self-focusing and the nonlinear focus moves upstream with increasing pulse energy. Behind the focus, elongated, gradually narrowing awl-shaped channels of electron-hole plasma and luminescent defects are produced. In the channels, whose dimensions generally depend on the pulse energy, supercontinuum emission propagating downstream the channels occurs, although its observation requires elevated pulse energies above 25 mu J in order to compensate energy dissipation in the channels. Ultrasonic side-view imaging of the channels, conducted from a few millimeters distance, reveals predominantly compressive pressure transients. The compressive signals are observed above the same threshold pulse energy E-opt, and their amplitude increases linearly with the laser pulse energy, simultaneously exhibiting significant temporal broadening of the corresponding pulsewidths, reflecting square root dependence of the channel length and sublinear (proportional to E-3/4) dependence of the source pressure on the pulse energy. Altogether, these optical and ultrasonic studies demonstrate filamentary pulse propagation with considerable dissipation (similar to 10 cm(-1)) in the awl-shaped subcritical plasma channels rich with generated point defects and optical damage sites. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3148249]
  • Hideo Iwase, Satoshi Kokubo, Saulius Juodkazis, Hiroaki Misawa
    OPTICS EXPRESS 17 6 4388 - 4396 2009年03月 [査読有り][通常論文]
     
    Gratings were recorded on the surface of nickel by ablation without formation of ripples using an interference of two p-polarized femtosecond laser beams at a pi/4 angle of incidence. The mechanism of ripples' suppression is explained by formation of a polarization grating and by ablation at the locations where the polarization is normal to the Ni surface. The aspect ratio of the ablated grooves was similar to 3 with the period similar to 570 nm at the central wavelength of irradiation of 800 nm. This method is applicable for laser structuring of different materials and a recorded grating structure can be scaled with the irradiation wavelength. (C) 2009 Optical Society of America
  • Yoshiaki Nishijima, Kosei Ueno, Saulius Juodkazis, Vygantas Mizeikis, Hideki Fujiwara, Keiji Sasaki, Hiroaki Misawa
    OPTICS EXPRESS 17 4 2976 - 2983 2009年02月 [査読有り][通常論文]
     
    Lasing in dye solution-embedded inverse silica opal structures was investigated. The opal films were prepared by sedimentation of polystyrene microspheres on a cover glass. The polystyrene structures were inverted using sol-gel infiltration of silica and subsequent removal of polystyrene. Photoluminescence of rhodamine ( rhodamine B, 6G and sulfo-rhodamine 101) dye solutions embedded into the inverse silica opal structures exhibited clear signatures of the lasing via a distributed feedback (DFB) and gain modulation. The refractive index contrast between the dye and the inverse opal was small enough (similar to 0.03%) for the formation of refractive index coupling between the lasing modes. The lasing spectrum exhibited a highly regular periodic structure of modal peaks, rather than the chaotic superposition of peaks reported in previous studies. Lasing modes having a spectral width of about 0.25 nm and a free spectral range of about 0.75 nm appeared at the position of the maximum gain ( the maximum fluorescence of the dye). (c) 2009 Optical Society of America
  • Hideki Nabika, Naozumi Iijima, Baku Takimoto, Kosei Ueno, Hiroaki Misawa, Kei Murakoshi
    ANALYTICAL CHEMISTRY 81 2 699 - 704 2009年01月 [査読有り][通常論文]
     
    A new methodology for nanoscopic molecular filtering was developed using a substrate with a periodic array of metallic nanogates with various widths between 75 and 500 nm. A self-spreading lipid bilayer was employed as the molecular transport and filtering medium. Dye-labeled molecules doped in the self-spreading lipid bilayer were filtered after the spreading less than a few tens of micrometers on the nanogate array. Quantitative analysis of the spreading dynamics suggests that the filtering effect originates from the formation of the chemical potential barrier at the nanogate region, which is believed to be due to structural change such as compression imposed on the spreading lipid bilayer at the gate. A highly localized chemical potential barrier affects the ability of the doped dye-labeled molecules to penetrate the gate. The use of the self-spreading lipid bilayer allows molecular transportation without the use of any external field such as an electric field as is used in electrophoresis. The present system could be applied micro- and nanoscopic device technologies as it provides a completely nonbiased filtering methodology.
  • Naoki Murazawa, Kosei Ueno, Vygantas Mizeikis, Saulius Juodkazis, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY C 113 4 1147 - 1149 2009年01月 [査読有り][通常論文]
     
    Qualitative resemblance between photopolymerization patterns induced in a commercial photoresist SU-8 by optical near-field of surface plasmons localized on rectangular gold nanorods was observed. This finding indicates the possibility of a fast qualitative near-field imaging by embedding metallic nanoparticle structures into photopolymerizeable media and examining the shapes of polymerized regions using high-resolution electron-scanning or atomic force microscopies following the optical exposure.
  • Etienne Brasselet, Tadas Balciunas, Naoki Murazawa, Saulius Juodkazis, Hiroaki Misawa
    MOLECULAR CRYSTALS AND LIQUID CRYSTALS 512 1989 - 1997 2009年 [査読有り][通常論文]
     
    We report on optically induced rotations of nematic liquid crystal droplets. We show experimentally that bipolar nematic liquid crystal droplets trapped in laser tweezers having circular polarization can exhibit nonlinear rotational motion, unlike optically trapped solid birefringent micro-plates. Such nonlinear rotations are retrieved by analyzing the polarization dynamics analysis of the light beam after it has passed through the droplet. The occurrence of complex dynamics is only found for large enough trapping power and droplet diameter. The analogy with optically induced nonlinear rotations in nematic liquid crystal films is briefly discussed.
  • S. Juodkazis, V. Mizeikis, Y. Nishijima, W. Ebina, H. Misawa, M. Kondo, V. Švrček
    ECS Transactions 16 41 57 - 63 2009年 [査読有り][通常論文]
     
    We report on the incorporation of silicon nanocrystals (nc-Si) into the photo-polymer resist SU8 by direct laser writing using femtosecond laser pulses and on the holographic formation of nano-/micro-textured surfaces by interference of several beams forming patterns with wide range of spatial frequencies. These approaches open possibility for a three-dimensional (3D) architectures of micro-structures potentially useful for active optical and fluidic micro-devices. © The Electrochemical Society.
  • Saulius Juodkazis, Hiroaki Misawa, G. Eugene Gamaly, V. Andrei Rode
    CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference 2009年 [査読有り][通常論文]
  • S. Juodkazis, E. G. Gamaly, V. Mizeikis, H. Misawa, A. V. Rode, W. Z. Krolikowski, K. Kitamura
    CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference 2009年 [査読有り][通常論文]
  • Vygantas Mizeikis, Rima Tarozaite, Saulius Juodkazis, Hiroaki Misawa
    ADVANCED FABRICATION TECHNOLOGIES FOR MICRO/NANO OPTICS AND PHOTONICS II 7205 2009年 [査読有り][通常論文]
     
    Metalo-dielectric photonic crystals (MDPC) were fabricated by the combination of direct laser writing technique, which was used to prepare initial dielectric templates, and by subsequent metalization of the templates using electroless coating technique. The obtained MDPC structures have adequate structural quality, and exhibit spectral signatures of photonic bands consistent with theoretical expectations. The fabrication process is simple but reliable, and can deliver MDPC structures suitable for operation in the infrared and terahertz spectral ranges.
  • Eugenijus Gaizauskas, Vygantas Mizeikis, Hiroaki Misawa, Sergey I. Kudryashov, Vladimir D. Zvorykin, Andrei A. Ionin, Saulius Juodkazis
    ULTRAFAST PHENOMENA IN SEMICONDUCTORS AND NANOSTRUCTURE MATERIALS XIII 7214 2009年 [査読有り][通常論文]
     
    Generation of free-carrier plasma and filamentation of the ultra-short laser pulse were investigated and modeled. Experimental results of filamentation are supported by numerical model which takes into account accumulation of refractive index modifications due to multi-pulse exposure. A contact acoustic monitoring technique was employed to perform spatially-resolved in situ detection of micro-plasma formation and filamentation of focused femtosecond laser pulses with critical and sub-critical powers in glass. The recorded acoustic signals reveal free-carrier generation mechanisms associated with the formation of plasma and filamentation of the propagating laser pulses. Optical opacity of the plasma region, which sets in at the irradiance of a few kJ/cm(3) (close to the dielectric breakdown threshold) using pulse focusing optics with numerical aperture NA = 0.75, reveals its critical character, and allows the estimation of acoustic pressure in the similar to GPa range. The pressure depended on the irradiance as P similar to I-0.59. In the case of loose focusing (NA = 0.035) filamentation of fs-pulses occurred at sub-critical plasma density with P similar to I. Detection and interpretation of these acoustic signatures thus enable real-time in situ monitoring of optical ionization, pulse filamentation in bulk dielectrics under the irradiation by femtosecond laser pulses.
  • 3P1-18
    Tomoda Motonobu, Matsueda Shinnosuke, Wright Oliver B, Matsuda Osamu, Nishijima Yoshiaki, Ueno Kosei, Saulius Juodkazis, Misawa Hiroaki
    Proceedings of Symposium on Ultrasonic Electronics 2009年 [査読無し][通常論文]
  • Saulius Juodkazis, Hiroaki Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 93 4 857 - 861 2008年12月 [査読有り][通常論文]
     
    The high-temperature annealing (1500 degrees C for 15 min) of the shock-amorphized and compressed sapphire around the voids rendered the amorphous sapphire insoluble in aqueous solution of hydrofluoric acid. There were no observable back relaxation and reflow of the compressed amorphous phase. The overlapping of femtosecond pulses by > 70% of the focal diameter also made the photomodified regions insoluble in aqueous solution of hydrofluoric acid. Femtosecond laser cutting of hard dielectric materials is discussed.
  • Koji Hatanaka, Ken-ichiro Yomogihata, Hiroshi Ono, Kei Nagafuchi, Hiroshi Fukumura, Michiko Fukushima, Tomohiro Hashimoto, Saulius Juodkazis, Hiroaki Misawa
    JOURNAL OF NON-CRYSTALLINE SOLIDS 354 52-54 5485 - 5490 2008年12月 [査読有り][通常論文]
     
    We have generated hard X-rays by front- and back-side femtosecond laser irradiation of PbO-rich glass. The actual Pb content of glasses was corroborated by Pb M-line emission intensities with an uncertainty of less than 20%. The elements K and As at concentrations of a few mol% were detected. X-ray generation by back-side irradiation helped to avoid an air breakdown; however, self-focusing and filamentation limited the achievable light intensity and effectiveness of X-ray generation. Characteristics and mechanisms of X-ray generation from the front- and back-side of glasses are discussed. (C) 2008 Elsevier B.V. All rights reserved.
  • Saulius Juodkazis, Yasufumi Nishi, Hiroaki Misawa
    PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS 2 6 275 - 277 2008年12月 [査読有り][通常論文]
     
    We report on wet etching of photomodified regions in crystalline sapphire using KOH solution. Tightly focused femtosecond laser pulses (150 fs at 800 nm wavelength) were used to create void structures enclosed in an amorphised sapphire shell inside the bulk of a crystalline host. The diameter of the amorphous regions can be controlled by pulse energy and was typically 0.5-1.5 mu m. The etching rate depends on the distance between adjacent irradiation spots, pulse energy, concentration of etchant and ultrasonic agitation.
  • Saulius Juodkazis, Vygantas Mizeikis, Markas Sudzius, Hiroaki Misawa, Kenji Kitamura, Shunji Takekawa, Eugene G. Gamaly, Wieslaw Z. Krolikowski, Andrei V. Rode
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 93 1 129 - 133 2008年10月 [査読有り][通常論文]
     
    We study experimentally the formation of refractive index voxels (volume elements) in photorefractive LiNbO3 and LiTaO3 crystals illuminated with high irradiance femtosecond laser pulses. We used 150 fs pulses at 800 nm wavelength (energy 6-50 nJ) tightly focused inside the crystals in a single shot regime. This resulted in a formation of a micrometer size region of elevated refractive index, which may be used as memory bits in information storage/retrieval application. The maximum refractive index change of 5x10(-4) was recorded in undoped LiNbO3 at an average light intensity of similar to TW/cm(2) that is close to the breakdown threshold. A simple setup for photorefractive recording and in situ monitoring of the refractive index changes has been proposed.
  • Kai Sun, Nobuko Suzuki, Zheyu Li, Ryoko Araki, Kosei Ueno, Saulius Juodkazis, Masumi Abe, Sumihare Noji, Hiroaki Misawa
    ELECTROPHORESIS 29 19 3959 - 3963 2008年10月 [査読有り][通常論文]
     
    A microchannel chip has been used to fractionate selected segments from an electrophoretic flow of separated fragments. A sample, which covers the size from 35 to 670 bp, was initially separated using an 8.8-cm-long channel at the electric field strength of 100 V/cm. The target fragment of 318 bp was selected and extracted from the separation channel. High-resolution fractionation was achieved by introducing new procedures for blocking, extraction, and segment transfer. Fractionation quality with and without blocking were compared using a 310 Genetic Analyzer (Applied Biosystems). The results show that no contamination was found in the sample, which was fractionated with blocking; however, a contamination by short segments was found in the sample, which was fractionated without blocking. Furthermore, fractionation by the chip was found to be of higher fidelity than that by the polyacrylamide slab gel, which displayed a small overlapped peak after the target peak. Compared with the traditional method, our chips enable faster and high-fidelity fractionation, thus providing a new toot for bioanalysis and other applications.
  • Yoshiaki Nishijima, Keisei Ueno, Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa, Mitsuru Maeda, Masashi Minaki
    OPTICS EXPRESS 16 18 13676 - 13684 2008年09月 [査読有り][通常論文]
     
    Lasing from zirconia inverse opal photonic crystal structures infiltrated by solutions of rhodamine dyes was found to exhibit single-mode lasing peaks with spectral width less than 1 nm and quality factor in excess of 4000. The lasing occurs within the approximate range of high-reflectance spectral region associated with photonic stop band along < 111 > crystallographic direction, but its wavelength is not fixed to the corresponding Bragg wavelength of the periodic structure, and depends on the spectral position of the gain band. This lasing regime can be useful for realizing tunable single-mode photonic crystal lasers. (c) 2008 Optical Society of America.
  • Kosei Ueno, Yukie Yokota, Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa
    CURRENT NANOSCIENCE 4 3 232 - 235 2008年08月 [査読有り][通常論文]
     
    We investigate functional capabilities of large arrays of gold and silver nanorods as elements of plasmonic devices. The samples were fabricated by electron beam lithography and lift-off techniques on glass substrates. The areas patterned by the nanorods or other nanoparticles can be large, with dimensions of up to about one centimeter. Structural and optical characterization has allowed confirmation of a high homogeneity of the fabricated ensembles of nanorods, and a high sensitivity of their longitudinal extinction bands to the variations of the nanorod length and the refractive index of the environment. Applications of nanorods as refractive-index sensors is discussed.
  • Koji Hatanaka, Takahito Ida, Hiroshi Ono, Shin-ichi Matsushima, Hiroshi Fukumura, Saulius Juodkazis, Hiroaki Misawa
    OPTICS EXPRESS 16 17 12650 - 12657 2008年08月 [査読有り][通常論文]
     
    The chirp effect on a X-ray emission intensity from a CsCl aqueous solution jet irradiated by femtosecond pulses was systematically studied. The p-polarized chirped pulses were more efficient as compared with the shortest pulses determined by the spectral bandwidth. The negatively-chirped pulses of approximately 240 fs duration produced up to 10 times larger X-ray intensity as compared with the transform-limited 160 fs pulses. The angular dependence of X-ray generation can be explained by the resonant absorption. Numerical simulations of electron density evolution due to the avalanche and multi-photon absorption supports qualitatively well the experimental observations. (c) 2008 Optical Society of America.
  • Mutsumi Takagi, Takayuki Kitabayashi, Satoru Koizumi, Haruka Hirose, Shin-ichi Kondo, Masashi Fujiwara, Kosei Ueno, Misawa Hiroaki, Yoichiroh Hosokawa, Hiroshi Masuhara, Shigeyuki Wakitani
    BIOTECHNOLOGY LETTERS 30 7 1189 - 1195 2008年07月 [査読有り][通常論文]
     
    A morphological parameter of polygonal index was defined as the ratio of cell adhesion area versus the square of the major cell axis, and cells that had an adhesion area larger than 4000 mu m(2) and a polygonal index larger than 0.3 were considered large polygonal cells. Cell morphology tended to change from fibroblast-like to polygonal and the percentage of the large polygonal cells increased almost in proportion to aggrecan mRNA expression level during the differentiation culture of mesenchymal stem cells (MSCs) to chondrocytes. Approximately 80% of the large polygonal cells were negative for MSC marker (CD90, CD166) expression and the aggrecan mRNA expression level of the large polygonal cells was markedly higher than that of cells with other morphologies.
  • Kock Khuen Seet, Vygantas Mizeikis, Kenta Kannari, Saulius Juodkazis, Hiroaki Misawa, Nicolas Tetreault, Sajeev John
    IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS 14 4 1064 - 1073 2008年07月 [査読有り][通常論文]
     
    This paper describes femtosecond laser lithography of 3-D photonic crystal templates in commercial photoresist SU-8 and replication of these templates with silicon. Using this approach, silicon-based photonic crystals having 3-D square spiral architecture and exhibiting photonic stop gaps near the 2.5-mu m wavelength were fabricated. Possibilities to use a multiple-beam interference technique for two-photon absorption templating of photonic crystals are explored.
  • Kosei Ueno, Saulius Juodkazis, Toshiyuki Shibuya, Yukie Yokota, Vygantas Mizeikis, Keiji Sasaki, Hiroaki Misawa
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 130 22 6928 - + 2008年06月 [査読有り][通常論文]
     
    We demonstrate the possibility to achieve optical triggering of photochemical reactions via two-photon absorption using incoherent light sources. This is accomplished by the use of arrays of gold nanoparticles, specially tailored with high precision to obtain high near-field intensity enhancement.
  • Eugene G. Gamaly, Saullus Juodkazis, Hiroaki Misawa, Barry Luther-Davies, Andrei V. Rode, Ludovic Hallo, Philippe Nicolai, Vladimir T. Tikhonchuk
    CURRENT APPLIED PHYSICS 8 3-4 412 - 415 2008年05月 [査読有り][通常論文]
     
    Formation of three-dimensional (3D) patterns of 0.2-0.5 mu m diameter voids inside a transparent solid has been demonstrated. The nano-voids could be created with a spacing similar to 2 mu m thus suggesting the possibility of permanent 3D optical memory with density similar to 100 Gbit/cm(3). Extremely high pressures of similar to 10 TPa and temperatures up to 10(5) K can be produced by a single sub-picosecond laser pulse tightly focused inside transparent dielectrics. Analysis of the size of the void and the shock affected zone as a function of the deposited energy shows that the experimental results can be explicitly understood on the basis of conservation laws and be modeled by plasma hydrodynamics. Therefore, the size of the void can be controlled and predicted by proper focusing conditions and laser parameters. (c) 2007 Elsevier B.V. All rights reserved.
  • Eugene G. Gamaly, Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa, Andrei V. Rode, Wieslaw Z. Krolikowski, Kenji Kitamura
    CURRENT APPLIED PHYSICS 8 3-4 416 - 419 2008年05月 [査読有り][通常論文]
     
    We report on a three-dimensional single-shot optical recording by 150 fs pulses at 800 nm wavelength in Fe-doped and stoichiometric undoped LiNbO3. The highest refractive index modulation of similar to 10(-3) per single pulse has been achieved at close to the dielectric breakdown irradiance of similar to TW/cm(2), and was found to be independent of polarization of the writing beam. The quasi-permanent and rewritable bits have been demonstrated in Fe-doped LiNbO3. Recording in undoped stoichiometric LiNbO3 was of transient nature with full optical contrast recovery on a 0.1-1 s scale. The observed refractive index modulation is explainable by the photovoltaic effect in LiNbO3. (c) 2007 Elsevier B.V. All rights reserved.
  • Etienne Brasselet, Naoki Murazawa, Saulius Juodkazis, Hiroaki Misawa
    Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 77 4 041704  2008年04月15日 [査読有り][通常論文]
     
    Laser manipulation of trapped radial 4′ -n-pentyl-4-cyanobiphenyl (5CB) nematic liquid-crystal droplets induced by molecular reordering is presented. We show experimentally that optical tweezers having linear, elliptical, or circular polarization can break the radial symmetry of the initial molecular organization inside a radial nematic droplet. Static distorted or twisted deformation modes and steady or unsteady nonlinear rotational dynamics are observed. Statics results are analyzed in terms of light-induced radial or left-right symmetry breaking effects associated with optical reorientation. The dynamical observations are compared with simulations from a slab analog model, for which orientational processes driven by optical nonlinearities can be accurately described. This study confirms that light-induced bulk reordering is an essential ingredient towards the understanding of the behavior of radial nematic liquid-crystal droplets in laser tweezers, as suggested by previous studies. © 2008 The American Physical Society.
  • Oleg A. Louchev, Saulius Juodkazis, Naoki Murazawa, Satoshi Wada, Hiroaki Misawa
    OPTICS EXPRESS 16 8 5673 - 5680 2008年04月 [査読有り][通常論文]
     
    A coupled mechanism for molecular aggregation in a thin water solution film by laser-tweezers is suggested based on (i) simulation of light intensity distribution and (ii) order of magnitude analysis of heat and mass transport induced by Marangoni convection. The analysis suggests that the laser induced temperature distribution develops within 1 ms and Marangoni convection flow commences within 0.01-1 s, which increases by 1-2 orders of magnitude the mass transfer of dissolved molecules into the laser focus where they are trapped and aggregate by attractive van der Waals forces. This mechanism, considered for the particular case of polymer assembly, suggests that it can also be successfully applied for assembling other types of clusters and molecular aggregates from solutions. (C) 2008 Optical Society of America.
  • Sergey I. Kudryashov, Vladimir D. Zvorykin, Andrei A. Ionin, Vygantas Mizeikis, Saulius Juodkazis, Hiroaki Misawa
    APPLIED PHYSICS LETTERS 92 10 101916  2008年03月 [査読有り][通常論文]
     
    Contact acoustic technique has been employed to perform spatially resolved in situ detection of microplasma formation and filamentation of tightly focused femtosecond laser pulses with supercritical pulse powers in bulk dielectrics, via corresponding acoustic emission. Investigation of acoustic generation mechanisms related to the plasma formation and filamentation effects reveals the critical character of the opaque microplasma and provides estimates of its gigapascal-level pressures and energy densities of a few kJ/cm(3). The acoustic measurement enables real-time in situ monitoring and revealing of basic mechanisms of ionization and filamentation in bulk dielectrics. (C) 2008 American Institute of Physics.
  • Toshiaki Kondo, Saullus Juodkazis, Vygantas Mizeikis, Hiroaki Misawa
    JOURNAL OF NON-CRYSTALLINE SOLIDS 354 12-13 1194 - 1197 2008年02月 [査読有り][通常論文]
     
    We demonstrate a method of capillary force reduction during wet processing of three-dimensional structures photo-polymerized in resist by femtosecond pulses. A rinse in water was added as the final step of wet processing for recovery of free-standing photo-polymerized structures with feature sizes of similar to 100 nm. The hydrophobicity of resist was utilized for reduction of the capillary drainage force. We show a possibility of holographical recording of a three-dimensional woodpile structure, which has a good permeability and can be fabricated by the proposed modified wet processing. (c) 2007 Elsevier B.V. All rights reserved.
  • Vygantas Mizeikis, Saulius Juodkazis, Markas Sudzius, Hiroaki Misawa, Eugene G. J. Gamaly, Andrei V. Rode, Wieslaw Z. Krolikowski, Kenji Kitamura
    PHOTONICS: DESIGN, TECHNOLOGY, AND PACKAGING III 6801 2008年 [査読有り][通常論文]
     
    We present experimental and theoretical study of refractive index modification induced by femtosecond laser pulses in photorefractive crystals. The single pulses with central wavelength of 800 nm, pulse duration of 150 fs, and energy in the range of 6-130 nJ, tightly focused into the bulk of Fe-doped LiNbO3 and stoichiometric LiTaO3 crystals induce refractive index change of up to about 10(-3) within the volume of about (2.0 x 2.0 x 8.0) mu m(3). The photomodification is independent of the polarization orientation with respect to the crystalline c-axis. The recorded region can be erased optically by a defocused low-intensity single pulse of the same laser. Recording and erasure can be repeated at the same position many times without loss of quality. These findings demonstrate the basic functionality of the ultrafast three-dimensional all-optical rewritable memory. Theoretically they are interpreted by taking into account electron photogeneration and recombination as well as formation of a space-charge field. The presented analysis indicates dominant role of photovoltaic effect for our experimental conditions, and suggests methods for controlling various parameters of the photomodified regions.
  • Kosei Ueno, Saulius Juodkazis, Vygantas Mizeikis, Keiji Sasaki, Hiroaki Misawa
    ADVANCED MATERIALS 20 1 26 - + 2008年01月 [査読有り][通常論文]
     
    Gold nanostructures consisting of nanoblocks separated by a few nanometer-wide gaps were fabricated, and found to exhibit strong photoluminescence due to enhancement of the optical near-field localized in the nanogaps. The fabricated structures demonstrate a nanostructured metallic material capable of efficient photoluminescence, whose efficiency can be adjusted by tailoring the nanogap width.
  • Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa
    PHOTORESPONSIVE POLYMERS I 213 157 - 206 2008年 [査読有り][通常論文]
     
    Optical techniques for three-dimensional micro- and nanostructuring of transparent and photo-sensitive materials are reviewed with emphasis on methods of manipulation of the optical field, such as beam focusing, the use of ultrashort pulses, and plasmonic and near-field effects. The linear and nonlinear optical response of materials to classical optical fields as well as exploitation of the advantages of quantum lithography are discussed.
  • Naoki Murazawa, Saulius Juodkazis, Hiroaki Misawa, Kenji Kamada
    Molecular Crystals and Liquid Crystals 489 310 - 319 2008年 [査読有り][通常論文]
     
    We report on excitation of photoluminescence via two-photon absorption (2PA) in dye-doped liquid crystal droplets using tightly focused cw-laser illumination at 1064nm wavelength. The photoluminescence of the 2PA dye C40H54N2O2 (MBAPB) dispersed inside the 7CB liquid crystal host increases as square of the laser tweezers' irradiance. The 2PA cross-section of MBAPB was measured by femtosecond Z-scan method. The polarization and temperature dependence of the photoluminescence corroborated the presence on the dye's molecular alignment inside the nonpolar liquid crystal host. The molecular alignment via the host-dye interaction can be used for the laser manipulation of micro-objects (e.g., doped liquid crystal droplets) in micro-fluidic/mechanical applications.
  • Kosei Ueno, Saulius Juodkazis, Vygantas Mizeikis, Dai Ohnishi, Keiji Sasaki, Hiroaki Misawa
    OPTICS EXPRESS 15 25 16527 - 16539 2007年12月 [査読有り][通常論文]
     
    Periodically corrugated chains of gold nanoblocks, fabricated with high precision by electron-beam lithography and lift-off techniques, were found to exhibit optical signatures of particle plasmon states in which relative contribution of longitudinal multipolar plasmons is significantly lower than that in equivalent rectangular gold nanorods. Plasmonic response of periodic chains is dominated by dipolar plasmon modes, which in the absence of multipolar exciations are seen as background-free and spectrally well-resolved extinction peaks at infrared (IR) wavelengths. This observation may help improve spectral parameters of IR plasmonic sub-wavelength antennae. Comparative studies of plasmon damping and dephasing in corrugated chains of nanoblocks and smooth rectangular nanorods are also presented. (C) 2007 Optical Society of America.
  • Saulius Juodkazis, Vygantas Mizeikis, Kock Khuen Seet, Hiroaki Misawa, Ulrike G. K. Wegst
    APPLIED PHYSICS LETTERS 91 24 241904-241904-3  2007年12月 [査読有り][通常論文]
     
    Mechanical properties of photopolymerized photonic crystal (PhC) structures having woodpile and spiral three-dimensional architectures were examined using flat-punch indentation. The structures were found to exhibit a foamlike response with a bend-dominated elastic deformation regime observed at strain levels up to 10%. Numerical simulations of optical properties of these PhC structures demonstrate the possibility of achieving a substantial and reversible spectral tuning of the photonic stop gap wavelength by applying a mechanical load to the PhC. (C) 2007 American Institute of Physics.
  • Y. Nishijima, K. Ueno, S. Juodkazis, V. Mizeikis, H. Misawa, T. Tanimura, K. Maeda
    OPTICS EXPRESS 15 20 12979 - 12988 2007年10月 [査読有り][通常論文]
     
    This work reports fabrication of inverse silica opal photonic crystal structures from direct polystyrene micro sphere opals using low-temperature sol-gel infiltration of silica, and examines performance of these photonic crystals as environmental refractive index sensors. Sensitivity of the spectral position and optical attenuation of photonic stop gaps is found to allow detection of the index changes by the amount of similar to 10(-3). The high value of sensitivity, which is comparable with those of other optical sensing techniques, along with simplicity of the optical detection setup required for sensing, and the low-temperature, energy-efficient fabrication process make inverse silica opals attractive systems for optical sensing applications. (c) 2007 Optical Society of America.
  • Naoki Murazawa, Saulius Juodkazis, Hiroaki Misawa, Hiroshi Wakatsuki
    OPTICS EXPRESS 15 20 13310 - 13317 2007年10月 [査読有り][通常論文]
     
    We report the trapping and manipulation of bubbles in viscous glass melts through the use of a laser. This phenomenon is observed in bubbles tens of micrometers in diameter under illumination by low numerical aperture ( NA = 0.55). Once the bubble was centered on the optical axis, it was trapped and followed a lateral relocation of the laser beam. This phenomenon is explained by modifications of the bubble's shape induced by axial heating and a decrease in surface tension. It is shown that formation of a concave dimple on the bubble's front surface explains the observed laser trapping and manipulation. This mechanism of laser trapping is expected to take place in other deformable materials and can also be used to remove bubbles from melts or liquids. For this technique to be effective, the alteration of the bubble's shape should be faster than its expulsion out of the laser's point of focus. (C) 2007 Optical Society of America.
  • Vygandas Jarutis, Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa
    PHYSICAL REVIEW A 76 4 043845  2007年10月 [査読有り][通常論文]
     
    Correlations between the entire conical spatial modes of signal and idler beams in a type II spontaneous parametric down-conversion (SPDC) under ultrashort pulse pumping are examined experimentally and theoretically. Statistical properties and theoretical analysis of "path-entangled" states formed using these beams suggest that the quantum state of SPDC photon pairs cannot be represented by a pure ensemble of identically prepared pairs.
  • Tomohiro Hashimoto, Saulius Juodkazis, Hiroaki Misawa
    NEW JOURNAL OF PHYSICS 9 253  2007年08月 [査読有り][通常論文]
     
    Void formation as a result of a single tightly focused femtosecond pulse irradiation has been systematically studied in commercial optical-grade glasses of different composition. Correlations between the composition, mass density, glass transition temperature and Young modulus of glass with the void formation threshold have been revealed. The pulse energy necessary to form a void was found reciprocal to the amount of glass-forming oxide in the case of silicate, phosphate and borate glasses. The larger is the bond strength ( the cohesion energy per bond) of the glass-forming oxide, the lower is the threshold energy of the pulse, at which the void is formed after a single pulse irradiation.
  • Kenji Kamada, Yoshihiko Tanamura, Kosei Ueno, Koji Ohta, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY C 111 30 11193 - 11198 2007年08月 [査読有り][通常論文]
     
    We report the enhancement of molecular two-photon absorption (2PA) of a dicationic 2PA chromophore (MPPBT) by confining it in a two-dimensional (2D) nanospace formed in nanolayered silicate clay by the cation exchange method in a water-dimethyl sulfoxide mixture. The 2PA property of the MPPBT/silicate nanocomposite prepared from the mixture by casting is characterized by the femtosecond open-aperture Z-scan method. We found that the 2PA cross-section of the chromophore in the nanocomposite is enhanced by a few times that of the dimethylsulfoxide solution at all wavelengths employed. This enhancement is accompanied by a bathochromic shift of the 2PA peak. The origin of this enhancement is discussed in terms of low dimensionality, suppressed internal twisting motion of the chromophore in the 2D confined space, and ionic interactions with the silicate surfaces.
  • Vygantas Mizeikis, Saulius Juodkazis, Rima Tarozaite, Jurga Juodkazyte, Kestutis Juodkazis, Hiroaki Misawa
    OPTICS EXPRESS 15 13 8454 - 8464 2007年06月 [査読有り][通常論文]
     
    We report structural and optical properties of three-dimensional periodic metallic woodpile structures obtained by direct laser writing in dielectric photoresist SU-8 and subsequent electroless coating by a thin Ni film. Signatures of photonic stop gaps were observed in optical reflection spectra of the structures at infrared wavelengths. This study demonstrates that the combination of DLWand chemical infiltration of metals is attractive as a simple and cost-efficient method for the fabrication of metalo-dielectric photonic crystals. (C) 2007 Optical Society of America
  • Kai Sun, Zheyu Li, Kosei Ueno, Saulius Juodkazis, Sumihare Noji, Hiroaki Misawa
    ELECTROPHORESIS 28 10 1572 - 1578 2007年05月 [査読有り][通常論文]
     
    We report the high fidelity on-chip fractionation of selected segrnents, from an electrophoretic flow of separated fragments. dsDNA fragments (10- 330 base pairs were initially separated using a 6.5 cm long channel with an electric field strength of 150 V/cm. As an example of the fractionation process, a target fragment of 20 bp was selected and extracted from the separation channel. The extraction was confirmed and evaluated by fluorescence imaging. High resolution and extraction fidelity were achieved by introducing new. procedures or (i) extraction channel-blocking and (ii) segment transfer with cleaning. These procedures are necessary for the development of a practical, fully automated multitarget fractionation electrophoretic chip. A kind of itCb image processing method was introduced to monitor, control, and evaluate the procedure of fractionation. The resolution limits of the separation and extraction are discussed.
  • Saulius Juodkazis, Koichi Nishimura, Hiroaki Misawa
    APPLIED SURFACE SCIENCE 253 15 6539 - 6544 2007年05月 [査読有り][通常論文]
     
    The actual space-time dependent intensity distribution of a tightly focused (numerical aperture NA = 1.35) Gaussian femtosecond pulse is modeled inside dielectric material. Such focusing is typically used for recording with sub-wavelength resolution inside dielectrics. The multi-pulse structuring inside the bulk and on the surface of sapphire are demonstrated. Formation of nano-cracks and nano-crystals is revealed inside the crystalline sapphire. Ripple formation on the surface is discussed in terms of the efficacy map calculated by theory given in ref. [J.E. Sipe, IF Young, J.S. Preston, H.M. van Driel, Laser-induced periodic surface structure. I. Theory, Phys. Rev. B 27 (2) (1983) 1141-1154.]. (C) 2007 Published by Elsevier B.V.
  • S. Juodkazis, N. Murazawa, H. Wakatsuki, H. Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 87 1 41 - 45 2007年04月 [査読有り][通常論文]
     
    We report on removal of micrometer-sized bubbles from molten glass by a 1064 nm wavelength cw-laser radiation focused using an objective lens of numerical aperture 0.55. The heating of a bubble and surrounding glass by tightly focused laser beam had reduced surface tension and caused disintegration of the bubble. Disintegration occurred at typically 1850 +/- 50 50 degrees C. Emission of a heated gas inside the bubble was used to determine the local temperature. Temporal evolution of the bubble disintegration was imaged by a CCD camera. Physics of the interaction between a focused laser beam and bubble is discussed.
  • Kosei Ueno, Saulius Juodkazis, Masahiro Mino, Vygantas Mizeikis, Hiroaki Misawa
    JOURNAL OF PHYSICAL CHEMISTRY C 111 11 4180 - 4184 2007年03月 [査読有り][通常論文]
     
    Uniform, ordered arrays of gold nanorods on glass substrates were fabricated with high accuracy using electron beam lithography and lift-off techniques. These structures exhibit longitudinal mode of localized surface plasmon (LSP) resonance with spectral position highly sensitive to the refractive index of local dielectric environment of the nanorods. The LSP resonance was found to red-shift nearly linearly, both with refractive index and aspect ratio of the nanorods, to the extent that enables optical detection of the refractive index changes of the order of 10(-2). The entire spectral range of the detection can be defined by tailoring size and aspect ratio of the nanorods during the fabrication and typically falls into the optical communications region. These structures are therefore promising as optical sensors enabling simple and efficient monitoring of chemical and biological processes.
  • M. Mazilu, S. Juodkazis, T. Ebisui, S. Matsuo, H. Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 86 2 197 - 200 2007年02月 [査読有り][通常論文]
     
    The presence of dislocations has been revealed by numerical processing of high-resolution transmission electron microscopy images from the regions affected by a shock wave propagation. The shock wave was triggered by a single 220 fs duration pulse of 30 nJ at an 800 nm wavelength inside sapphire at approximately 10 mu m depth. The shock-amorphised sapphire has a distinct boundary with the crystalline phase, which is not wet etchable even at a dislocation density of similar or equal to 8 x 10(12) cm(-2).
  • Saulius Juodkazis, Koichi Nishimura, Hiroki Okuno, Yusuke Tabuchi, Shigeki Matsuo, Satoru Tanaka, Hiroaki Misawa
    INTERNATIONAL CONFERENCE ON LASERS, APPLICATIONS, AND TECHNOLOGIES 2007: LASER-ASSISTED MICRO- AND NANOTECHNOLOGIES 6732 67320B/1-10  2007年 [査読有り][通常論文]
     
    We demonstrate three - dimensional (3D) structuring of materials by femtosecond laser irradiation. The self-organized ordered formation of ripples by a laser raster-scanning on the surface of 4H-SiC is demonstrated. This method is scalable up to areas with sum-millimeter cross-sections. The role of ripple-like structures in the case of the surface and in-bulk micro-structuring of different materials is discussed. The field enhancement effects at the nano-structured surfaces and their role in ripple formation are estimated.
  • Saulius Juodkazis, Andrei V. Rode, Toshiaki Kondo, Hiroaki Misawa, Marek Samoc, Barry Luther-Davies
    MATERIALS AND PROCESSES FOR NONVOLATILE MEMORIES II 997 357 - + 2007年 [査読有り][通常論文]
     
    The nonlinear absorption coefficient of As2S3 glass has been measured to be 2.0 cm/GW for femtosecond pulses at 800 nm. Femtosecond laser structuring via two photon absorption in bulk As2S3 glass by erasable and permanent photo-darkening is demonstrated using both holographic and direct multi-beam laser writing.
  • Three-dimensional Laser Structuring of Materials at Tight Focusing
    S. Juodkazis, K. Nishimura, H. Misawa
    Chinese Opt. Lett. 5 S198 - S200 2007年 [査読有り][通常論文]
  • Yukie Yokota, Kosei Ueno, Vygantas Mizeikis, Saulius Juodkazis, Keiji Sasaki, Hiroaki Misawa
    JOURNAL OF NANOPHOTONICS 1 011594/1-15  2007年 [査読有り][通常論文]
     
    Highly homogeneous arrays of Ag, Au and Cu nanorods were fabricated on glass substrates using electron-beam lithography and lift-off techniques. Optical properties of the fabricated structures related to localized surface plasmons (LSP), and their dependencies on the nanorod size were studied experimentally by optical extinction spectroscopy. Spectral tuning of LSP resonant scattering bands in a wide spectral range, from visible to near-infrared wavelengths, can be accomplished by tailoring of the nanorod dimensions, aspect ratios, and heights. The observed results qualitatively agree with Gans theory and numerical modeling by finite-difference time-domain technique.
  • Saulius Juodkazis, Hiroaki Misawa, Eugene G. Gamaly, Barry Luther-Davies, Andrei V. Rode, Ludovic Hallo, Phillipe Nicolai, Vladimir T. Tikhonchuk
    SHOCK COMPRESSION OF CONDENSED MATTER - 2007, PTS 1 AND 2 955 1041 - + 2007年 [査読有り][通常論文]
     
    Extremely high pressure (similar to 10 TPa) and temperature (5 X 10(5) K) have been produced using a single laser pulse (similar to 100 nJ, 800 nm, 200 fs) focused inside transparent dielectrics. The laser pulse of intensity over 0.1 PW/cm(2) converts a material within the absorption volume of similar to 0.15 mu m(3) into plasma in a few fenitoseconds. A pressure of similar to 10 TPa, far exceeding the strength of any material builds up to the end of the pulse generating strong shock and rarefaction waves. This results in the formation of a nano-void surrounded by a shell of shock-compressed material. In sapphire, the compressed shell revealed that it has a density 1.14 times of the initial one and increased chemical reactivity. The unique conditions: extreme pressure and temperature at record high heating and cooling rates become available in a well-controlled laboratory environment.
  • O. A. Louchev, S. Juodkazis, H. Misawa, K. Kitamura
    INTERNATIONAL CONFERENCE ON LASERS, APPLICATIONS, AND TECHNOLOGIES 2007: LASER-ASSISTED MICRO- AND NANOTECHNOLOGIES 6732 2007年 [査読有り][通常論文]
     
    Formation of nano-fibers ranging from 30 to 300 nm in diameter and exceeding the length of one millimeter was observed during explosive ablation of As2S3 glass by femtosecond pulses at high fluence (> 5 J/cm(2)) irradiation of the 800 nm wavelength, 160 fs duration pulses in air. However, the spheres of up to several microns in diameter are found to form competing with nano-fiber formation and significantly deteriorating their morphology. The formation of these pheres is explained by the free energy minimization of explosively ablating liquid jets combined with the onset and evolution of the thermo-capillary forces at the local perturbations of the geometry and temperature. Performed thermal analysis suggests that the good nano-fiber morphology can be preserved by increasing the air pressure or ablation in water which shortens the characteristic cooling and solidification time of the liquid jets, and inhibits the development of the small geometrical perturbations into the large spheres.
  • Saulius Juodkazis, Hiroaki Misawa, Egidijus Vanagas, Mingwei Li
    JOURNAL OF LASER MICRO NANOENGINEERING 1 3 253 - 257 2006年12月 [査読有り][通常論文]
     
    A high-precision 3D structuring of dielectrics by sub-1 ps pulses is possible by dielectric breakdown and opens an unique possibility to create a high temperature electrons inside material under processing. The 3D nano/micro-structuring by dielectric breakdown is numerically simulated by 3D finite-differences time domain (FDTD) calculations where the plasma is simulated by a nano-sphere of metal (gold). The effect of anisotropic light scattering in the plane of incident polarization has been qualitatively explained by light inteaction with ionized (metalic) focal volume. It is shown that the experimentaly achieved densification of materials after irradiation by tightly focused sub-1 ps pulses is consistent with formation of new high-pressure phases.
  • Kosei Ueno, Saulius Juodkazis, Vygantas Mizeikis, Keiji Sasaki, Hiroaki Misawa
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 128 44 14226 - 14227 2006年11月 [査読有り][通常論文]
  • Saulius Juodkazis, Hiroaki Misawa, Oleg A. Louchev, Kenji Kitamura
    NANOTECHNOLOGY 17 19 4802 - 4805 2006年10月 [査読有り][通常論文]
     
    Formation of nano-fibres ranging from 30 to 300 nm in diameter and exceeding the length of one millimetre was observed during explosive ablation of As2S3 glass by femtosecond pulses at high fluence (> 5 J cm(-2)) irradiation of the 800 nm wavelength, 160 fs duration pulses in air. Spheres of up to several microns in diameter were also found to form, competing with nano-fibre formation and significantly deteriorating their morphology. Theoretical analysis of thermo-capillary and heat exchange mechanisms of the fibre formation predicts conditions under which the good nano-fibre morphology can be preserved.
  • Toshiaki Kondo, Saulius Juodkazis, Vygantas Mizeikis, Shigeki Matsuo, Hiroaki Misawa
    NEW JOURNAL OF PHYSICS 8 250 2006年10月 [査読有り][通常論文]
     
    Three-dimensional (3D) periodic dielectric structures were recorded in a commercial photoresist SU-8 by exposure to intensity patterns created by five interfering coherent femtosecond Ti : sapphire laser pulses. Periodic symmetry of these patterns was controlled by the choice of mutual convergence angles of the beams as well as their phases. The fabricated structures are mechanically and chemically stable, well-connected frameworks of SU-8 regions in air; the smallest dimensions of SU-8 features are in the sub-micrometre range. The structures exhibit a high degree of long-range order across areas as large as 1 mm in cross-section.
  • Takeshi Araki, Kousei Ueno, Hiroaki Misawa, Noboru Kitamura
    ANALYTICAL SCIENCES 22 10 1283 - 1289 2006年10月 [査読有り][通常論文]
     
    Temperature-dependent phase-vanishing processes between perfluorohexane (FC-72) and n-heptane (C7H16, volume ratio of 1:1 and phase-vanishing temperature >41 degrees C), were studied in a glass microchannel-microheater chip under solution-flow conditions. Without applying a voltage to the heater at 21 C, the two liquids in the microchannel were separated into two streams at a solution flow rate (v) of 0.975 cm/s, while the phase boundary between FC-72 and C7H16 vanished in the downstream side of the heater at V = 4.5 V. Then, we conducted Raman intensity imaging during the phase vanishing processes in the microchannel by monitoring the band at 756 (FC-72) or 1456 cm(-1) (C7H16). At V = 4.5 V and v = 0.975 cm/s, although no phase boundary between the two liquids in the microchannel was observed, the relevant Raman intensity images indicated the inhomogeneous nature of the solution, and distribution of C7H16 to the FC-72 phase along with solution flow was observed.
  • Saulius Juodkazis, Markas Sudzius, Vygantas Mizeikis, Hiroaki Misawa, Eugene G. Gamaly, Youwen Liu, Oleg A. Louchev, Kenji Kitamura
    APPLIED PHYSICS LETTERS 89 6 062903  2006年08月 [査読有り][通常論文]
     
    The authors report on a three-dimensional single-shot optical recording by 150 fs pulses at 800 nm wavelength in Fe doped LiNbO3. The rewritable bits (2(x)x2(y)x8(z) mu m(3)) are demonstrated. The highest refractive index modulation of similar to 10(-3) per single pulse has been formed by preferential photovoltaic effect at close to the dielectric breakdown irradiance of similar to TW/cm(2) and was independent of polarization (in respect to the c axis). The achievable refractive index modulation is evaluated and the recording mechanisms are discussed. (c) 2006 American Institute of Physics.
  • Toshiaki Kondo, Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa, Shigeki Matsuo
    OPTICS EXPRESS 14 17 7943 - 7953 2006年08月 [査読有り][通常論文]
     
    Micro-fabrication of periodic structures was performed by holographic lithography technique in SU-8 photoresist using a simple and versatile experimental arrangement based on a diffractive beam-splitter. High-fidelity two-and three-dimensional microstructures fabricated with sub-micrometric resolution in large areas of approximately 1 mm diameter. The structures are potentially usable as elements of micro-fluidic systems (e. g., Brownian ratchets), and templates for photonic crystal devices (e. g., mirrors, collimators, superprisms).
  • Saulius Juodkazis, Toshiaki Kondo, Hiroaki Misawa, Andrei Rode, Marek Samoc, Barry Luther-Davies
    OPTICS EXPRESS 14 17 7751 - 7756 2006年08月 [査読有り][通常論文]
     
    The nonlinear absorption coefficient of As2S3 glass has been measured to be 2.0 cm/GW for femtosecond pulses at 800 nm. Femtosecond laser structuring via two photon absorption in bulk As2S3 glass by erasable and permanent photo-darkening is demonstrated using both holographic and direct multi-beam laser writing. (c) 2006 Optical Society of America.
  • N. Murazawa, S. Juodkazis, H. Misawa
    EUROPEAN PHYSICAL JOURNAL E 20 4 435 - 439 2006年08月 [査読有り][通常論文]
     
    The laser trapping of a smectic-A liquid-crystal micro-droplet was spatially traced during its transient into the trapped position. The lateral and angular orientation of the droplet were determined and followed in time during the axial descent of the micro-droplet into the stationary trapped position using the analysis of polarization changes of the light passed through the droplet with temporal resolution of a video refresh rate of 30 ms. The spatial resolution of 0.1-1 mu m has been achieved for typical laser trapping powers of 2-600 mW. The axial profile of a laser trapping force (an ellipticity of the focal spot) has been determined. The laser trapping mechanism of smectic micro-droplets is discussed in terms of minimization of a light-droplet interaction.
  • S Matsuo, Y Tabuchi, T Okada, S Juodkazis, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 84 1-2 99 - 102 2006年07月 [査読有り][通常論文]
     
    In quartz crystal substrates, microchannels were made by femtosecond laser assisted etching, i.e., irradiation of focused femtosecond laser pulses followed by wet etching. By the use of wet etching, the laser irradiated region was selectively etched out, and a microchannel was formed inside the quartz substrate. The laser irradiated region was found to be amorphous by transmission electron microscopy. Anisotropy in the etching rate inside the quartz was observed.
  • Kock Khuen Seet, Vygantas Mizeikis, Saulius Juodkazis, Hiroaki Misawa
    JOURNAL OF NON-CRYSTALLINE SOLIDS 352 23-25 2390 - 2394 2006年07月 [査読有り][通常論文]
     
    Photonic crystal structures having three-dimensional (3D) circular spiral architecture have large theoretical photonic band-gap but cannot be implemented by most of the existing microfabrication techniques. We have successfully used a highly versatile 3D microstructuring technique called femtosecond laser microfabrication to prepare templates of the circular spiral photonic crystals in a commercially available photoresist SU-8. The structures fabricated have good structural quality, are highly periodic and exhibit spectral signatures of photonic bands dispersion in the short infrared wavelength region. (c) 2006 Elsevier B.V. All rights reserved.
  • Kock Khuen Seet, Saulius Juodkazis, Vygandas Jarutis, Hiroaki Misawa
    APPLIED PHYSICS LETTERS 89 2 024106-1 - 024106-3 2006年07月 [査読有り][通常論文]
     
    The universal scaling of a width of photopolymerized line on the exposure dose was observed in polymerization by direct laser writing using tightly focused femtosecond pulses in SU-8 resist. This scaling can be explained as the photopolymerization by a blackbody-type emission. A spectrally broad thermal emission of electrons heated up to temperatures approximately T-e similar to 10(3) K coincides with an IR-absorption band of SU-8 centered at the 2.9 mu m and had caused polymerization by a cumulative direct absorption. Three-dimensional photonic crystal templates with approximately twice reduced feature size were fabricated with stop band at the fiber communication wavelength of 1.3 mu m. (c) 2006 American Institute of Physics.
  • Saulius Juodkazis, Hiroaki Misawa
    3D Laser Microfabrication: Principles and Applications 379 - 385 2006年06月29日 [査読有り][通常論文]
  • S Juodkazis, K Nishimura, H Misawa, T Ebisui, R Waki, S Matsuo, T Okada
    ADVANCED MATERIALS 18 11 1361 - + 2006年06月 [査読有り][通常論文]
     
    Amorphous regions in sapphire with sub-micrometer 3D resolution have been produced at the focus of a single femtosecond laser pulse. Crystalline-to-amorphous and amorphous-to-polycrystalline transitions (crystalline and amorphous regions are marked C and A in the HRTEM image) are induced by single- and multi-pulse irradiation, respectively. The wet-etching selectivity for the amorphous phase is significantly greater than that for the crystalline phase in aqueous HF.
  • H. Segawa, S. Yamaguchi, Y. Yamazaki, T. Yano, S. Shibata, H. Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 83 3 447 - 451 2006年06月 [査読有り][通常論文]
     
    Two-dimensional (2D) pillar arrays with submicrometer to micrometer repetitions have been fabricated from hybrid organic-inorganic material by mask lithography or multi-beam interference lithography. The type of array structure depends on structural parameters such as the pillar height, diameter and distance between neighboring pillars. Two kinds of periodic arrays, 2D arrays and 'top-gathering' arrays, can be obtained by controlling the structural parameters. In the top-gathering arrays, the pillars are gathered at the top by means of self-organization, and 'top-gathering' units composed of four pillars can be formed.
  • EG Gamaly, S Juodkazis, K Nishimura, H Misawa, B Luther-Davies
    PHYSICAL REVIEW B 73 21 214101  2006年06月 [査読有り][通常論文]
     
    We present here the experimental and theoretical studies of a single femtosecond laser pulse interaction inside a bulk of transparent media (sapphire, glass, polymer). This interaction leads to the drastic transformations in a solid resulting in a void formation inside a dielectric. The laser pulse energy is absorbed within a volume of approximately 0.15 mu m(3) creating a pressure and temperature comparable to that in the core of a strong multi-kilo-tons explosion. The material within this volume is rapidly atomized, ionized, and converted into a tiny super-hot dense cloud of expanding plasma that generates strong shock and rarefaction waves which result in the formation of a void, whose diameter is similar to 200 nm (for a 100 nJ pulse in sapphire). The way this structure forms can be understood from high-temperature plasma hydrodynamics. We demonstrate that unique states of matter characterized by temperatures similar to 10(5) K, heating rates up to the 10(18) K/s, and pressures more than 100 times the strength of any material were created using a standard table-top laser in well-controlled laboratory conditions. We discuss the properties of the laser-affected solid and possible routes of laser-affected material transformation to the final state long after the pulse end. These studies will find application for the design of new materials and three-dimensional optical memory devices, and for formation of photonic band-gap crystals.
  • T Hashimoto, S Juodkazis, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 83 2 337 - 340 2006年05月 [査読有り][通常論文]
     
    We report on the formation of voids of 200-300 nm in diameter by single femtosecond pulses (800 nm/150 fs/ < 100 nJ) inside silica glass. The mechanism of void formation can be understood in terms of dielectric breakdown and shock wave formation. The voids were recorded below the threshold of self-focusing. Diffraction efficiency of gratings recorded by arranging voids into a pattern of open core channels have shown an interesting tendency of an increasing efficiency for the first five diffraction orders. It is demonstrated by numerical simulation using the finite difference time domain (FDTD) algorithm that such anomalous diffraction is indeed caused by empty core channels surrounded by densified shells inside silica.
  • S Juodkazis, H Misawa, T Hashimoto, EG Gamaly, B Luther-Davies
    APPLIED PHYSICS LETTERS 88 20 201909  2006年05月 [査読有り][通常論文]
     
    We report on the nanovoid formation inside synthetic silica, viosil, by single femtosecond pulses of 30-100 nJ energy, 800 nm wavelength, and 180 fs duration. It is demonstrated that the void is formed as a result of shock and rarefaction waves at pulse power much lower than the threshold of self-focusing. The shock-compressed region around the nanovoid is demonstrated to have higher chemical reactivity. This was used to reveal the extent of the shock-compressed region by wet etching. Application potential of nanostructuring of dielectrics is discussed. (c) 2006 American Institute of Physics.
  • K. K. Seet, V. Mizeikis, S. Juodkazis, H. Misawa
    Appl. Phys. Lett. 88 22 221101  2006年05月 [査読有り][通常論文]
     
    Three-dimensional photonic crystals with a circular spiral architecture were fabricated by direct laser writing (DLW) in a photoresist. DLW was performed with a laser beam having the direction of propagation and elongation of the ellipsoidal focal region perpendicular to the spirals' orientation. This allowed the reduction of the turning period of the spirals while avoiding the overlap between their adjacent turns. Consequently, optical transmission and reflection spectra of the fabricated samples revealed multiple photonic stop gaps whose shortest wavelength was 0.88 mu m, the lowest observed so far in spiral structures. These results were qualitatively reproduced by finite-difference time-domain simulations. This fabrication scheme can be useful for DLW of structures where photonic stop gaps along particular directions, rather than complete photonic band gaps, are required. (c) 2006 American Institute of Physics.
  • S Juodkazis, K Nishimura, S Tanaka, H Misawa, EG Gamaly, B Luther-Davies, L Hallo, P Nicolai, VT Tikhonchuk
    PHYSICAL REVIEW LETTERS 96 16 166101  2006年04月 [査読有り][通常論文]
     
    Extremely high pressures (similar to 10 TPa) and temperatures (5x10(5) K) have been produced using a single laser pulse (100 nJ, 800 nm, 200 fs) focused inside a sapphire crystal. The laser pulse creates an intensity over 10(14) W/cm(2) converting material within the absorbing volume of similar to 0.2 mu m(3) into plasma in a few fs. A pressure of similar to 10 TPa, far exceeding the strength of any material, is created generating strong shock and rarefaction waves. This results in the formation of a nanovoid surrounded by a shell of shock-affected material inside undamaged crystal. Analysis of the size of the void and the shock-affected zone versus the deposited energy shows that the experimental results can be understood on the basis of conservation laws and be modeled by plasma hydrodynamics. Matter subjected to record heating and cooling rates of 10(18) K/s can, thus, be studied in a well-controlled laboratory environment.
  • KK Seet, Mizeikis, V, S Juodkazis, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 82 4 683 - 688 2006年03月 [査読有り][通常論文]
     
    Three-dimensional photonic crystals consisting of periodic arrays of spiral columns were fabricated in a commercially available photoresist (SU-8) by a direct laser writing technique. Tailoring the pre- and post-processing conditions for the photoresist has enabled the recording of extended, self-supporting periodic structures with sub-diffraction resolution. Pronounced photonic stop gaps were observed at wavelengths between 1.5 and 1.8 mu m, close to the telecommunications region. These structures can be used as accurate and robust templates for subsequent infiltration by materials with higher refractive index.
  • N Murazawa, S Juodkazis, Jarutis, V, Y Tanamura, H Misawa
    EUROPHYSICS LETTERS 73 5 800 - 805 2006年03月 [査読有り][通常論文]
     
    We demonstrate that the viscosity measurement by a spinning laser-trapped liquid-crystal microsphere depends on the surface tension and hydrophobicity of sphere's material. A reduction of the viscous drag was observed for the hydrophobic E44 liquid-crystal droplets even at low surface tension, while a reduced surface tension caused an increased drag in the case of 5CB microspheres. The importance of the non-slipping boundary condition and light propagation throughout the laser-trapped microsphere in the viscosity measurements by a spinning microsphere (Bishop A. I. et al., Phys. Rev. Lett., 92 (2004) 198104) is discussed.
  • T Mizuno, Y Tanamura, K Yamasaki, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 45 3A 1640 - 1647 2006年03月 [査読有り][通常論文]
     
    We report photoacid-induced nonerasable recording in tert-butoxycarbonyl-protected quinizarin methacrylate polymers for three-dimensional optical memory. 1 m/s-speed recording was achieved using an 800nm femtosecond laser at an 80MHz-repetition rate, without a postexposure bake after laser irradiation. Three-layer recording indicates that no optical damage during recording enables modulation of the Compact Disc type memory. The linewidth of recorded marks of 0.4 mu m indicates a 49 Gbits/cm(2) areal density when the numerical aperture is 1.35.
  • N Murazawa, S Juodkazis, H Misawa
    OPTICS EXPRESS 14 6 2481 - 2486 2006年03月 [査読有り][通常論文]
     
    We report on a novel principle of actuation of micrometer-sized liquid crystal droplets. It is based on a light-induced reordering of liquid crystal molecules inside the droplets. Polariscope imaging allowed to evaluate the birefringence change inside the micro-droplets. Directional actuation of the trapped droplet was achieved by cycling laser power with the direction defined by the polarization of the tweezing beam. Micro-actuation resulted from optically-induced birefringence; i.e., a nonlinear optical effect was utilized for mechanical manipulation of the micro-droplet. This principle of actuation can be used to induce molecular flows in sub-micrometer volumes. (c) 2006 Optical Society of America.
  • N Murazawa, S Juodkazis, Y Tanamura, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 45 2A 977 - 982 2006年02月 [査読有り][通常論文]
     
    We demonstrated that viscosity measurement using a spinning laser-trapped microsphere depends on the hydrophobicity or hydrophylicity of a spherical material. Reduction in viscous drag was observed in hydrophobic liquid crystal droplets. Rheology on a liquid crystal surface with D2O was demonstrated by spinning and stopping a laser tweezed droplet. The importance of nonslipping boundary conditions in viscosity measurements is discussed.
  • Naoki Murazawa, Saulius Juodkazis, Hiroaki Misawa
    OPTICAL TRAPPING AND OPTICAL MICROMANIPULATION III 6326 1 - 9 2006年 [査読有り][通常論文]
     
    We demonstrate laser manipulation of different nematic and smectic liquid crystal droplets in heavy water. Peculiarities of laser trapping and manipulation depending on the molecular structure of liquid crystal are discussed. Possibility of molecular reordering inside the tweezed droplet is demonstrated. This phenomenon can be used to induce the birefringence and to manipulate droplets, which have a small birefringence, e.g., a radial droplet of negligible birefringence can be turned into a birefringent one at high laser trapping power. This is a demonstration of the optical nonlinear effect being responsible for a micro-mechanical phenomenon such as spinning of the droplet in a circularly polarized laser tweezers. Three-photon absorption of MBAPB dye at 1064 nm wavelength is demonstrated inside the liquid crystal droplet at comparatively low similar to 60 MW/cm(2) intensity.
  • Saulius Juodkazis, Hiroaki Misawa
    FEMTOSECOND PHENOMENA AND NONLINEAR OPTICS III 6400 1 - 8 2006年 [査読有り][通常論文]
     
    The mechanism of three-dimensional (3D) laser micro-structuring of dielectrics (resists, polymers, glasses, and crystals) by the direct laser writing is discussed. Overview of a light-matter interaction of a tightly-focused femtosecond pulse with dielectrics is presented. The void formation is demonstrated inside silica glass by a single picosecond pulse. Peculiarities of tight focusing and an axial superposition of two co-propagating pulses at the focus are revealed by numerical simulations. Potential of the fabricated 3D patterns in micro-photonics, micro-fluidics, and sensor applications is discussed.
  • E Gaizauskas, E Vanagas, Jarutis, V, S Juodkazis, Mizeikis, V, H Misawa
    OPTICS LETTERS 31 1 80 - 82 2006年01月 [査読有り][通常論文]
     
    Filamentation of Bessel-Gauss pulses propagating in borosilicate glass is found to produce damage lines extending over hundreds of micrometers and consisting of discrete, equidistant damage spots. These discrete damage traces are explained by self-regeneration of Gauss-Bessel beams during propagation and are potentially applicable in laser microfabrication of transparent materials. (c) 2006 Optical Society of America.
  • S Juodkazis, E Gaizauskas, Jarutis, V, J Reif, S Matsuo, H Misawa
    JOURNAL OF PHYSICS D-APPLIED PHYSICS 39 1 50 - 53 2006年01月 [査読有り][通常論文]
     
    We report on a novel phenomenon occurring when ultrashort laser pulses are diffracted in a Bragg grating recorded in a photo-thermo-refractive glass: two intense beams at the third harmonic of the incident laser frequency appear between the direct and the diffracted laser beams. A high conversion efficiency of about 0.04% at an incident intensity of 5 x 10(11) W cm(-2) in a 1 mm thick grating is attributed to self-phase matching for the third harmonic generation via Cherenkov radiation from the interfering third order polarization of the incident and diffracted beams. It is assumed that this is a general phenomenon for diffraction in a volume grating.
  • Kock Khuen Seet, Toshiaki Kondo, Vygantas Mizeikis, Vygandas Jarutis, Saulius Juodkazis, Hiroaki Misawa
    Proceedings of SPIE - The International Society for Optical Engineering 6161 2006年 [査読有り][通常論文]
     
    The physical principles underlying the three-dimensional (3D) laser microstructuring technique are outlined, its applications for the fabrication of 3D photonic crystals are described. Structures recorded by direct laser writing and holographic recording techniques in SU-8 photoresist are presented along with their structural and optical characterization.
  • S Juodkazis, Mizeikis, V, E Gaizauskas, E Vanagas, Jarutis, V, H Misawa
    INTERNATIONAL CONFERENCE ON LASERS, APPLICATIONS, AND TECHNOLOGIES 2005: HIGH-POWER LASERS AND APPLICATIONS 6053 2006年 [査読有り][通常論文]
     
    Self-focusing and filamentation of nearly-Gaussian femtosecond laser pulses propagating in photosensitive silicate glass was investigated. The filamentation was visualized by the precipitation of NaF nano-crystallites along the beam pass after post-exposure treatment of photosensitive glass, which provides a direct proof that ionization of silicate matrix takes place along the filament propagation lines. Theoretical model of the multi-filamentation based on the propagation of a Gaussian beam with elliptical transverse intensity profile modulated by a spatial noise in a medium with multi-photon absorption is proposed. Self-action of the ferntosecond Gaussian-Bessel pulses in borosilicate glass was observed at high fluence. This model reproduces qualitatively the dotted damage lines observed after the beam propagation in borosilicate glass.
  • Sauhus Juodkazis, Mingwei Li, Dmitry Kotin, Igor Maksimov, Egidijus Vanagas, Hiroaki Misawa
    ULTRAFAST PHENOMENA IN SEMICONDUCTORS AND NANOSTRUCTURE MATERIALS X 6118 2006年 [査読有り][通常論文]
     
    Thermal effects are unavoidable in laser material processing and are present, to some extent, even in the case when ultra-short (sub-picosecond) pulsed irradiation is used. We discuss here the matters of high-precision energy delivery into micrometer-sized volumes for three-dimensional (3D) laser microfabrication. Precise account of the absorbed energy, pulse duration, and focal spot size allows to optimize laser processing parameters. As an example, a 3D micro-structuring of silica with better than 15 mu m resolution is demonstrated by pulses of 11 ns duration and 266 nm wavelength (for a focusing by a low numerical aperture NA = 0.029 lens). The two photon absorption coefficient of silica, beta similar or equal to 60 +/- 10 cm/GW, at 266 nm has been determined. The thermal black-body type emission of non-equilibrated electrons is discussed as a possible light source for 3D modification and structuring of photo-sensitive and photo-polymerizable materials. It is also demonstrated that optical properties of ionized dielectrics can be used to determine the temperature.
  • Hiroyo Segawa, Hiroaki Misawa, Tetsuji Yano, Shuichi Shibata
    PHOTON PROCESSING IN MICROELECTRONIC AND PHOTONICS V 6106 2006年 [査読有り][通常論文]
     
    Multi-beam laser interference (MLI) lithography is known to be one of the fabrication techniques of photonic crystals. In MLI lithography laser beams are interfered on a scale of the wavelength of light and are irradiated to photosensitive films. We have paid attention to photosensitive TiO2-organic hybrid film, which has high refractive index. TiO2-organic hybrid periodic pillar patterns were fabricated by MLI lithography. The TiO2) hybrid film, which was prepared from Ti-alkoxide and beta-diketone by the sol-gel method, was exposed to the interference pattern of femtosecond pulses at 800 run wavelength. After laser irradiation, the unirradated portion was removed by the development and rinse. Two-dimensional periodic standing alone pillars and 2 x 2 and 3 x 3 top-gathering pillars, which were gathered at the top by means of self-organization were formed by changing conditions such as laser irradiation time and film thickness. The pillar patterns depended upon the rinse liquid, the diameter, and the height of pillars. The top-gathering pillars are applicable for diffractive optics.
  • T Kondo, S Juodkazis, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 81 8 1583 - 1586 2005年12月 [査読有り][通常論文]
     
    The wet processing of SU8 resist was modified in order to achieve a high-aspect ratio patterning with feature size of 100 nm. A final rinse in water, which makes a large contact angle on the resist (less wetting) was added to the procedure. This allowed considerable reduction of the capillary force, which is responsible for pattern distortions in three-dimensional (3D) lithography. 3D recording of high-aspect ratio (f(ar)=18) structures by holographic exposure using femtosecond pulses in SU8 resist was achieved using this modified development procedure. The thickness of the free-standing planes was approximately 100 nm. High fidelity of this recording method was confirmed by a Moire pattern transfer into a developed SU8 pattern. In terms of focusing, the 100 nm feature size comprised 1/13-th of the diffraction limit. This modified development is applicable for wet processing when super-critical drying cannot be used.
  • E Vanagas, JY Ye, M Li, M Miwa, S Juodkazis, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 81 4 725 - 727 2005年09月 [査読有り][通常論文]
     
    Stress/strain around the line recorded inside borosilicate glass was investigated by polarization microscopy. Thermal accumulation effects were observed during in-bulk recording. The relevance of the phenomena for laser scribing and dicing applications is discussed.
  • T Mizuno, K Yamasaki, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 44 9A 6593 - 6595 2005年09月 [査読有り][通常論文]
     
    We report a photoacid-induced write-once read-many recording medium based on poly(methyl methacrylate) for three dimensional (3D) optical memory, Three-layered recording was achieved using only an 800 nm-femtosecond oscillator with a 82-MHz-repetition rate without structural damage. Bits of arbitrary length used in the present modulation method of Compact Disc type memory can be recorded by photo-modification in the medium. The results suggest that the medium is an attractive candidate to solve the technical problems of 3D recording, in which micro-structural integrity of medium is altered.
  • N Murazawa, S Juodkazis, H Misawa
    JOURNAL OF PHYSICS D-APPLIED PHYSICS 38 16 2923 - 2927 2005年08月 [査読有り][通常論文]
     
    Bipolar and radial droplets of 4-pentyl-4'-cyanobiphenyl were manipulated using circularly polarized laser-tweezers. Light-induced birefringence arising from orientational nonlinearity was observed and measured for the radial droplets. The highest laser trapping power used 0.5 W induced a birefringence of 0.02 and hence the spinning of the droplets was observed.
  • K Ueno, Mizeikis, V, S Juodkazis, K Sasaki, H Misawa
    OPTICS LETTERS 30 16 2158 - 2160 2005年08月 [査読有り][通常論文]
     
    We report on control over the extinction spectrum of tetragonal gold nanoblocks by changing their lateral aspect ratio. Nanoblocks were patterned on a glass substrate by electron-beam lithography and were 40-400 mn in lateral dimensions and spanned from 1 to 9 in aspect ratio. This allowed us to tune the localized surface plasmon bands from 700 nm to 1.5 mu m (longitudinal mode) and from 700 to 550 mu m (transverse mode). Unprecedented polarization selectivity of the transverse and longitudinal plasmon bands was achieved via alignment and 3D control of the dimensions of the nanoblocks. (c) 2005 Optical Society of America.
  • VV Datsyuk, S Juodkazis, H Misawa
    PHYSICAL REVIEW A 72 2 025803  2005年08月 [査読有り][通常論文]
     
    The rate of spontaneous electromagnetic emission in a cavity is the normalized output radiation rate in the classical electrodynamics and the Einstein A coefficient in a quantum theory. We reveal the difference and similarity between the quantum and classical rates by calculations of the relative output power of the resonant spontaneous electric-dipole emission as a function of light absorption in a high-Q cavity. We show that the relative resonant output power is equal to the relative width of a morphology-dependent resonance in the spectral dependence of the Einstein A coefficient. The validity of the theory is demonstrated by numerical verification of an experimental result on a microsphere.
  • VV Datsuyk, S Juodkazis, H Misawa
    JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS 22 7 1471 - 1478 2005年07月 [査読有り][通常論文]
     
    The criteria for lasing in a dielectric sphere surrounded by an active medium are given. They are presented in simple analytical form and confirmed by numeric calculations of the amplitudes of the morphology-dependent resonances in spontaneous emission spectra. The determined lasing threshold of this novel-type laser is compared with that of a conventional spherical laser with an optically active internal layer. The diverse advantages of a laser based on the gain of the evanescent part of a whispering-gallery mode are discussed. (c) 2005 Optical Society of America.
  • S Juodkazis, Mizeikis, V, KK Seet, M Miwa, H Misawa
    NANOTECHNOLOGY 16 6 846 - 849 2005年06月 [査読有り][通常論文]
     
    Studies on two-photon lithography in negative SU-8 photoresist demonstrate the possibility of obtaining mechanically stable, stress-free, extended nanorods having lateral sizes of about 30 nm (corresponding to lambda/25 resolution). The high resolution achievable with the given combination of materials and fabrication techniques demonstrates its potential for the fabrication of large-scale nanostructures, such as photonic crystals with photonic stop gaps at visible wavelengths.
  • A Takita, H Yamamoto, Y Hayasaki, N Nishida, H Misawa
    OPTICS EXPRESS 13 12 4560 - 4567 2005年06月 [査読有り][通常論文]
     
    We realized optical data storage in a human fingernail. A structural change is recorded by irradiating a focused femtosecond laser pulse and is read out with fluorescent observation by making use of an increased fluorescence intensity. The shape of the structural changes drastically depends on the irradiated pulse energy. The fluorescence spectrum of the structure coincided with the auto-fluorescence spectra of a fingernail and a heated fingernail. It is suggested that the increased fluorescence is most likely caused by a local denaturation of the keratin protein by the femtosecond laser pulse irradiation. We demonstrate that the increased fluorescence effect is useful for reading out three-dimensionally recorded data. (C) 2005 Optical Society of America.
  • N Murazawa, S Juodkazis, S Matsuo, H Misawa
    SMALL 1 6 656 - 661 2005年05月 [査読有り][通常論文]
     
    Here, we demonstrate how the light-induced birefringence due to the dipole molecular realignment and anisotropic polarizability of a nematic liquid crystal inside a droplet changes the droplet's radial (and thus optically isotropic) structure into a birefringent one. This intensity-dependent change of birefringence can be understood in terms of the anisotropic polarizability and orientational optical nonlinear effect. Birefringence induced by laser tweezers changes the momentum of the passing light. In turn, for the circularly polarized tweezers, this change generates an angular momentum change large enough to spin micrometer-sized droplets. For the linearly polarized tweezers, the molecular ordering generates momentum, which laterally displaces the droplet. It is shown that the optical nonlinearity can be "large" enough to have mechanical (ponderomotive) implications, that is, it allows control of the movement and position of micro-objects with submicrometer resolution. The optically induced molecular alignment controlled by the polarization and power of the laser tweezers allows one to actuate, rotate, and translate objects which are up to 10(3)-10(4) times larger than the constituent molecules themselves.
  • T Masuda, A Yamaguchi, M Hayashida, F Asari-Oi, S Matsuo, H Misawa
    SENSORS AND ACTUATORS B-CHEMICAL 105 2 556 - 561 2005年03月 [査読有り][通常論文]
     
    We propose a novel detection method for a duplex formation of DNA on a solid substrate. In this method, DNA monolayers are prepared on a gold thin film, and then the substrate is treated by an etching process. Since the DNA monolayer can act as a resist layer, the thickness of the gold film in the regions covered by DNA monolayers is larger than that in the region without the monolayer. Furthermore, the difference in the resistance effect of ss- and ds-DNA monolayers induces the difference in the thickness of the gold thin film after the etching. The resistance effect of the ss-probe DNA monolayer increases as a result of the formation of a duplex with the target DNA. The sequence-specific hybridization adsorption of the target DNA can be detected visually by measuring the light transmittance of the gold film, or with the naked eye. Using this method, we succeeded in detecting two base pair mismatches in a 30-base pair nucleotide. (c) 2004 Elsevier B.V. All rights reserved.
  • KK Seet, Mizeikis, V, S Matsuo, S Juodkazis, H Misawa
    ADVANCED MATERIALS 17 5 541 - + 2005年03月 [査読有り][通常論文]
     
    A recently elaborated novel class of spiral-architecture photonic crystals, which has promising photonic bandgap properties, is realized by direct laser writing in SU-8 (see Figure). Such self-supporting structures show signatures of photonic stopgaps at infrared wavelengths, and can serve as accurate templates for infiltration of higher-refractive-index materials.
  • K Ueno, M Hayashida, JY Ye, H Misawa
    ELECTROCHEMISTRY COMMUNICATIONS 7 2 161 - 165 2005年02月 [査読有り][通常論文]
     
    Interdigitated nanoelectrode arrays with controlled electrode bandwidth and gap geometries ranging from 30 nm to 1 mum were fabricated on glass substrates by a planar process involving high resolution electron beam lithography and lift-off, and their characteristic electrochemical responses to an aqueous ferrocene derivative solution were examined using fundamental electrochemical techniques. Despite the comparatively large electrode area of electrode arrays containing 10 bands to a single band electrode, quasi-steady-state currents with high current density were obtained at a slow potential sweep rate in cyclic voltammograms of ferrocene derivative since the lateral dimension of the nanoelectrode arrays was considerably less than the scale of the diffusion layer of redox species. Additionally, it was demonstrated that the electrode thickness influenced limiting currents of voltammograms in the case of nanoelectrode arrays. In generation-collection mode experiments, furthermore, a collection efficiency as high as similar to99% was attained by 100 nm wide electrode arrays with a gap dimension of 30 nm. (C) 2004 Elsevier B.V. All rights reserved.
  • S Matsuo, S Juodkazis, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 80 4 683 - 685 2005年02月 [査読有り][通常論文]
     
    A microlens array (MLA) was applied for femtosecond laser microfabrication. Two-dimensional periodic patterns that corresponded to the arrangement of lenses in the MLA were recorded by ablation on a glass surface. The two-dimensional periodic patterns were recorded by a single exposure without scanning of the laser beam or the sample, and worked as a grating. Optical resizing of the patterns and high efficiency of fabrication are demonstrated and discussed.
  • Jarutis, V, S Juodkazis, Mizeikis, V, K Sasaki, H Misawa
    OPTICS LETTERS 30 3 317 - 319 2005年02月 [査読有り][通常論文]
     
    A method of enhancing the efficiency of entangled biphoton sources based on a type II femtosecond spontaneous parametric downconversion (SPDC) process is proposed and implemented experimentally. Enhancement is obtained by mode inversion of one of the SPDC output beams, which allows the beams to overlap completely, thus maximizing the number of SPDC photon pairs with optimum spatiotemporal overlap. By use of this method, biphoton count rates as high as 16 kHz from a single 0.5-mm-long beta-barium borate crystal pumped by second-harmonic radiation from a Ti:sapphire laser were obtained. (C) 2005 Optical Society of America.
  • M Hayashida, A Yamaguchi, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS 44 50-52 L1544 - L1546 2005年 [査読有り][通常論文]
     
    In this study, we demonstrate the use of surface plasmon interaction between Au nanoparticles (GPs) and a Au thin film for enhancement of surface plasmon resonance (SPR) spectroscopy sensing for DNA hybridization. In situ DNA hybridization with a Au-nanoparticle-attached probe DNA (DNA-GP) monolayer is monitored by SPR spectroscopy, and the results reveal that the DNA-GP allows detection of unlabeled target DNA with the large dynamic range of 1 pM to 10 mu M.
  • V. Jarutis, S. Juodkazis, V. Mizeikis, H. Misawa
    IQEC, International Quantum Electronics Conference Proceedings 2005 1008 - 1009 2005年 [査読有り][通常論文]
     
    The method allowing enhance the eficiency of entangled photon sources based on Type II spontaneous parametric down conversion (SPDC) by means of mode inversion of one of the SPDC output beams is described. Overlap between the the entire signal in idler beams can be achieved using the mode inversion thus maximizing the SPDC photon pair yields. With this method, coincidence count rates as high as 60 kHz from a single 0.5 mm long bulk BBO crystal pumped by the second-harmonic radiation of a femtosecond Ti: Sapphire laser, were obtained.
  • Kock Khuen Seet, Vygandas Jarutis, Saulius Juodkazis, Hiroaki Misawa
    Proceedings of SPIE - The International Society for Optical Engineering 6050 2005年 [査読有り][通常論文]
     
    The physical principles underlying a three-dimensional (3D) laser microstructuring technique are outlined, its applications for the fabrication of 3D (nano)micro-structured materials are presented. The direct laser writing and holographic recording in SU-8 photoresist are described. The limits of the lateral and axial light localization of a Gaussian pulse/beam at the focus are derived for the multi-photon absorption taking into account the threshold of photomodification. Prospective holographic patterns formed by interference of circularly and linearly polarized beams are discussed.
  • Y Tanamura, K Kamada, H Misawa
    2005 PACIFIC RIM CONFERENCE ON LASERS AND ELECTRO-OPTICS 859 - 860 2005年 [査読有り][通常論文]
     
    We have developed highly efficient two-photon absorption (TPA) materials, which are consisted of organic TPA dye and inorganic nanolayered silicate (clay). Linear and nonlinear optical characterization for the TPA materials ware carried out.
  • Mizeikis, V, KK Seet, S Juodkazis, Jarutis, V, H Misawa
    2005 PACIFIC RIM CONFERENCE ON LASERS AND ELECTRO-OPTICS 1037 - 1038 2005年 [査読有り][通常論文]
     
    High quality three-dimensional micro-and nano-structures were fabricated in photoresist SU-8 by two-photon laser lithography. Extended periodic microstructures with so-called woodpile architecture are demonstrated to have good quality and exhibit fundamental and higher-order photonic stop-gaps in the infrared wavelength range of 2.0-8.0 mu m. These SU-8 structures can be used as photonic crystal templates suitable for infiltration by high refractive index materials. To illustrate the resolution limit of SU-8 material, we also demonstrate fabrication of SU-8 nanorods with ultrahigh resolution of about 30 nm.
  • N Murazawa, S Juodkazis, Jarutis, V, Y Tanamura, H Misawa
    2005 PACIFIC RIM CONFERENCE ON LASERS AND ELECTRO-OPTICS 855 - 856 2005年 [査読有り][通常論文]
     
    We demonstrate the viscosity measurement using laser-trapped liquid crystal droplet. The viscosity, determined experimentally depended on die diameter of the droplet and boundary conditions at the liquid crystal surface which was changed by adding surfactant.
  • KK Seet, Mizeikis, V, S Juodkazis, H Misawa
    2005 PACIFIC RIM CONFERENCE ON LASERS AND ELECTRO-OPTICS 1035 - 1036 2005年 [査読有り][通常論文]
     
    Spiral architecture photonic crystals have been fabricated in a negative-tone photoresist SU-8 by direct laser writing. These photonic crystals are self-supporting and highly-periodic, and exhibit photonic attenuation in the range of 1.7 to 5.0 mu m..
  • K Ueno, Mizeikis, V, S Juodkazis, K Sasaki, H Misawa
    2005 PACIFIC RIM CONFERENCE ON LASERS AND ELECTRO-OPTICS 857 - 858 2005年 [査読有り][通常論文]
     
    Two-photon excited fluorescence of organic dye by embedding them with gold nanostructures fabricated on a glass substrate was enhanced on the basis of increasing electromagnetic field induced by nanogap configuration.
  • E Vanagas, E Gaizauskas, Mizeikis, V, Jarutis, V, S Juodkazis, H Misawa
    2005 PACIFIC RIM CONFERENCE ON LASERS AND ELECTRO-OPTICS 848 - 848 2005年 [査読有り][通常論文]
     
    Light filament formation in borosilicate glass under femtosecond pulse irradiation was investigated. The main observations were successfully reproduced by numerical modeling.
  • Mizeikis, V, KK Seet, S Juodkazis, Jarutis, V, H Misawa
    Ultrafast Lasers for Materials Science 850 149 - 154 2005年 [査読有り][通常論文]
     
    High quality templates of three-dimensional photonic crystals were fabricated in photoresist SU-8 using femtosecond laser lithography. The templates have woodpile and spiral architectures, which are widely expected to yield spectrally wide and robust photonic band gaps. Their opt characterization reveals fundamental and higher-order photonic stop-gaps in the infrared wavelength range of 2.0-8.0 mu m. These templates are mechanically stable, nearly free of shrinkage-related deformations, and can be used for subsequent infiltration by optically active or high refractive index materials.
  • H Segawa, H Misawa
    2005 PACIFIC RIM CONFERENCE ON LASERS AND ELECTRO-OPTICS 978 - 979 2005年 [査読有り][通常論文]
     
    Two-dimensional periodic pillar arrays have been produced from titania-organic hybrid film by multi-beam laser interference technique. The period of the arrays can be controlled by the laser energy and film thickness.
  • Y Hayasaki, H Takagi, A Takita, H Yamamoto, N Nishida, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 43 12 8089 - 8093 2004年12月 [査読有り][通常論文]
     
    We investigated the processing of a human fingernail surface using a tightly focused femtosecond laser pulse. The processed structure in the fingernail surface is strongly dependent on the focus position and irradiation energy of the single laser pulse. We observed a ring, a simple pit, a small pit with a surrounding uplift, an irregular jagged surface, and a swell containing a void, depending on the focus position. We also observed a sudden change in the size of the processed structure according to the irradiation pulse energy. From a linear theoretical estimation based on the diffraction of the laser beam, we found that the sudden change is primarily due to the diffraction pattern generated by the circular aperture of the objective lens. We also describe the processing features by comparing the structures processed in a fingernail with those processed in glass.
  • S. Juodkazis, I. Maksimov, H. Misawa
    J. App. Phys. 96 11 6934 - 6936 2004年12月 [査読有り][通常論文]
     
    Photonic crystal structures consisting of dielectric cylinders arranged in a honeycomb pattern were fabricated in silicon using electron-beam lithography and inductively-coupled plasma dry-etching. Lattice parameters of the fabricated structures (rod diameter similar to0.4 mum, distance between the centers of neighboring rods similar to0.85 mum, and rod height similar to5.2 mum) allowed to achieve and confirm experimentally the complete photonic band gap in vicinity of the optical communications wavelengths around 1.5 mum. (C) 2004 American Institute of Physics.
  • S Juodkazis, H Misawa, Maksimov, I
    APPLIED PHYSICS LETTERS 85 22 5239 - 5241 2004年11月 [査読有り][通常論文]
     
    In-bulk recording without cracking in borosilicate glass by high repetition rate (80 MHz) 12 ps pulses at 355 nm wavelength is demonstrated and discussed. The theoretical model of a "hot-line" scan and thermal accumulation qualitatively well describes the experimental results. The analytical expression of a thermally induced stress was obtained. (C) 2004 American Institute of Physics.
  • H Segawa, J Tabuchi, K Yoshida, S Matsuo, H Misawa
    JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY 32 1-3 287 - 291 2004年10月 [査読有り][通常論文]
     
    Photosensitive organic-titania hybrid materials have been prepared from metal alkoxides and various organic ester compounds with C=C double bonds. The refractive index of the film increases with the decrease of the concentration of the organic ester compound, and the highest refractive index of 1.62 is obtained when 2-hydroxymethyl acrylate (HOA) is used as the organic ester and the molar ratio of HOA to Ti is 0.5. The material with the highest refractive index is exposed to femtosecond pulse using the multi-beam laser interference technique. After laser irradiation, the irradiated parts of the material are photopolymerized and periodic structures can be obtained by development of the unirradiated parts. In the case of laser irradiation of 120 mu J total energy for 5 min, the periodic structure obtained corresponds to 2D photonic crystal structure which is composed of two parts; the material with the highest refractive index and the air.
  • S Juodkazis, H Okuno, N Kujime, S Matsuo, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 79 4-6 1555 - 1559 2004年09月 [査読有り][通常論文]
     
    We report on the ablation and hole drilling in stainless steel SUS304 and Si by femtosecond pulses (wavelength 800 nm; pulse duration >80 fs) at the room and low (5 Torr) air pressure ambient. It was found that the quality of surface processing is improved at low pressure avoiding debris formation. The improvement is due to suppression of the conical emission, resulting from the air optical breakdown at a pre-surface area of sample. Debris-free processing of the movable Si-MEMS components is demonstrated. Techniques for the precise measurement of focal spot size and pulse duration are discussed.
  • S Juodkazis, K Yamasaki, Mizeikis, V, S Matsuo, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 79 4-6 1549 - 1553 2004年09月 [査読有り][通常論文]
     
    Channel formation in glasses is demonstrated and discussed. Photosensitive glass (Foturan) was microstructured using femtosecond irradiation at 800 nm and 400 nm wavelengths, with subsequent thermal annealing, and HF etching of a lithium-silicate phase formed by exposure-annealing. It was found that there is a significant difference in the volume of lithium-silicate when the exposure was made with and without optical breakdown. Channels with a minimum cross section of approximately 10 mum were achieved. In silicate glasses, the optically induced dielectric breakdown was used for the recording of channel patterns. The highest wet etching rate in a HF based solution was observed when the irradiance corresponded to the 2.5-3.0 thresholds of dielectric breakdown and the adjacent pulses were overlapping by more than 50% of the diameter of the focussed beam. Under these conditions, the formation of a void inside the glass was confirmed by optical observation of single shot damage under a microscope. The mechanism of selective wet etching in silicate glasses is discussed in terms of the stress corrosion effect, which explains crack propagation in glasses via the reaction of stretched Si-O-Si bonds at the tip of a crack with water, resulting in SiOH formation. It is shown that intra-connection of voxels was the key factor to achieve etching of high aspect ratio patterns in silica glass.
  • Mizeikis, V, KK Seet, S Juodkazis, H Misawa
    OPTICS LETTERS 29 17 2061 - 2063 2004年09月 [査読有り][通常論文]
     
    High-quality templates of three-dimensional woodpile photonic crystals are fabricated in photoresist SU-8 by use of femtosecond laser lithography. The samples have smooth surfaces, are mechanically stable, and are resistant to degradation under environmental and chemical influences. Fundamental and higher-order photonic stopgaps are identified in the wavelength range 2.0-8.0 mum. These templates can be used for subsequent infiltration by optically active or high-refractive-index materials. (C) 2004 Optical Society of America.
  • H Segawa, S Matsuo, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 79 3 407 - 409 2004年08月 [査読有り][通常論文]
     
    TiO2-organic hybrid dot arrays were produced from TiO2-organic hybrid films by a multi-beam laser interference technique of ferntosecond laser pulses. The hybrid films were prepared from titanium alkoxide and beta-diketonate by the sol-gel method. Films were exposed to interference light from fermosecond pulses which have an intensity distribution over the pitch of the order of a micron. The chemical structures of the hybrid film were changed by multi-photon absorption from femtosecond pulses, and made chemical patterning possible after the development process. The precursor arrays of the TiO2-organic hybrid material were calcined at 450degreesC. TiO2-organic hybrid dot arrays with a refractive index of 2 were obtained.
  • S Juodkazis, H Misawa
    JOURNAL OF MICROMECHANICS AND MICROENGINEERING 14 8 1244 - 1248 2004年08月 [査読有り][通常論文]
     
    We report on ablation of complex micro-patterns on/in polymethylmethacrylate (PMMA) microspheres of 2-7 mum diameter. By controlling the irradiation fluence, different ablation patterns can be reproduced: (i) the ablation of the opposite side to that irradiated, (ii) two-side ablation along the propagation of the beam and (iii) a through-hole ablation of the PMMA microsphere. Microspheres were laser trapped and held by tightly focused cw-illumination at 1064 nm while the ablation was carried out by a coaxial irradiation of a single laser pulse of 7 ns duration at 355 nm wavelength. Calculations of spatial intensity distribution of Mie light scattering by a laser-trapped microsphere corroborated the ablation patterns observed experimentally. Laser microfabrication of through-holes in microspheres is explained by the ablation-triggered shock waves. The ponderomotive action of the laser beam is discussed.
  • Mizeikis, V, Mikulskas, I, R Tomasiunas, S Juodkazis, S Matsuo, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 43 6A 3643 - 3647 2004年06月 [査読有り][通常論文]
     
    The optical properties of two-dimensional photonic crystals (PhCs) in anodic aluminum oxide (AAO) films obtained using a simple and low-cost pre-patterning procedure are described. The prepatterning of the initial Al film surface was carried out by imprinting with an optical diffraction grating; the anodization of the prepatterned sample led to the formation of a good quality, large-area PhC with a triangular lattice of air holes (lattice period a = 0.48 mum, hole radius r = 0.2 mum) in an AAO film. The optical transmission spectra of the sample were measured at visible wavelengths in the range of 0.4-1.0 mum for various incidence angles and linear polarizations of the probing light. The detailed analysis of the transmission data indicates a photonic band gap in the 0.9-1.0 mum wavelength range for light waves linearly polarized in the direction perpendicular to the axes of PhC pores.
  • HC Liu, A Yamaguchi, M Hayashida, S Matsuo, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 43 5A 2767 - 2770 2004年05月 [査読有り][通常論文]
     
    We have developed a sensitive detection system for DNA hybridization containing DNA-Au nanoparticles (DNA-GPs) multilayer which leads to the enhancement of the detection sensitivity of surface plasmon resonance (SPR) signals. The SPR angular shift, which is the difference in the SPR angles before and after hybridization, becomes amplified with increasing number of layers of the DNA-GPs. A similar increase in SPR angular shift was obtained for the target DNA with low concentration. The reason for the enhancement is attributed to the interaction between Au nanoparticles and the Au film, as well as the increase in immobilized probe DNA content on the substrate.
  • T Kondo, K Yamasaki, S Juodkazis, S Matsuo, Mizeikis, V, H Misawa
    THIN SOLID FILMS 453 550 - 556 2004年04月 [査読有り][通常論文]
     
    We report femtosecond laser microfabrication in thin films of polymeric photoresists by (i) direct laser writing and (ii) holographic recording techniques. With (i) we have fabricated empty microchannels in polymethylmethacrylate; the channel width closely follows the intensity distribution in the focal spot of a high numerical aperture lens in accordance with scalar and vectorial Debye theory. With (ii) we have fabricated free-standing two-dimensional periodic structures in SU8 photoresist. The structures contain cylindrical pillars with noticeable ripple-like modulation of their diameter along their axes. This modulation results from the interference between the waves incident on the sample and back-reflected from the glass substrate or air, and is explained using an appropriate numerical modeling. (C) 2003 Elsevier B.V. All rights reserved.
  • O Efimov, S Juodkazis, H Misawa
    PHYSICAL REVIEW A 69 4 042903  2004年04月 [査読有り][通常論文]
     
    We show that the threshold power density of the intrinsic laser-induced damage in borosilicate glass at similar to1 mum wavelength does not depend on pulse duration from 2x10(-13) to 3x10(-8) s and has the same value for both single- and multiple-pulse exposure of the sample. This indicates that the mechanism of the intrinsic damage in glasses involves a collective response of a certain volume in the dielectric as a whole, such as "dielectric-metal" phase transition, rather than a process of individual generation and accumulation of electrons, such as multiphoton, tunneling, or avalanche. Also, we demonstrate that under femtosecond exposure the threshold of the plasma formation in transparent glasses is considerably higher than the threshold of the residual change of medium parameters.
  • E Vanagas, J Kawai, D Tuzhilin, Kudryashov, I, A Mizuyama, KG Nakamura, KI Kondo, SY Koshihara, M Takesada, K Matsuda, S Juodkazis, Jarutis, V, S Matsuo, H Misawa
    JOURNAL OF MICROLITHOGRAPHY MICROFABRICATION AND MICROSYSTEMS 3 2 358 - 363 2004年04月 [査読有り][通常論文]
     
    We report on quartz and glass cutting by a lateral scanning of femtosecond pulses (150 fs at 1 kHz repetition rate) of 800 nm wavelength at room and low pressure (5 Torr) air ambience. Pulses were focused by a low numerical aperture (NAless than or equal to0.1) objective lens. Optimization of fabrication conditions: pulse energy and scanning speed were carried out to achieve large-scale (millimeter-to-centimeter) cutting free of microcracks of submicron dimensions along the edges and walls of the cut. Cutting through out the samples of 0.1-0.5 mm thickness was successfully achieved without apparent heat affected zone. At low air pressure (5 Torr) ambience, redeposition of ablated material was considerably reduced. It is demonstrated that the damage on the rear surface was induced by the stress waves, which originated from the plasma ablation pressure pulse. The mechanism of femtosecond-laser cutting of transparent materials at high irradiance and the influence of stress waves generated by plasma plume are discussed. (C) 2004 Society of Photo-Optical Instrumentation Engineers.
  • S Juodkazis, T Kondo, A Rode, S Matsuo, H Misawa
    FIFTH INTERNATIONAL SYMPOSIUM ON LASER PRECISION MICROFABRICATION 5662 179 - 184 2004年 [査読有り][通常論文]
     
    We report on three-dimensional (3D) holographic recording in AS(2)S(3) glass using 800 nm wavelength, 150 fs duration pulses. Diffractive beam splitter was used to generate 2 - 5 beams which were then focused for recording by objective lens of numerical aperture NA = 0.75. The recorded 3D hologram was read out by diffraction of 632 nm HeNe laser beam confirming the expected pattern of holograms. The mechanism of photo-darkening and optical damaging of AS(2)S(3) glass and dielectrics in general is discussed. Two-photon absorption cross-section, sigma(2) = 74.6 x 10(-50) cm(4)/(S), was determined by transmission for pulses of 150 fs and 800 nm wavelength. Also, it is demonstrated that the optical damage threshold scales as the bandgap energy for the fluorides. Nano-/ rnicro-structuring of AS(2)S(3) glass by ablation in air will be also demonstrated. High fluence ( > 5 J/cm(2)) irradiation of the 800 ran wavelength, 150 fs duration pulses was used to ablate AS(2)S(3) glass. Self-organized growth of the fibers, rods, and microsphere-type structures was observed. Composition of the nano-/micro-structured material was close to that of the source AS(2)S(3) glass (with up to 20% surplus of sulphur in nano-rods). Straight rods as thin as 20 nm in diameter and over 1 pm-long were obtained. Application potential of nano-/microstructured AS(2)S(3) glass is discussed.
  • Mizeikis, V, KK Seet, S Juodkazis, H Misawa
    FIFTH INTERNATIONAL SYMPOSIUM ON LASER PRECISION MICROFABRICATION 5662 95 - 100 2004年 [査読有り][通常論文]
     
    Three-dimensional woodpile photonic crystal structures were recorded in films of polymeric photoresists polymethylcrylate (PMMA) and SU-8 films by femtosecond laser microfabrication technique. The fabricated structures consist of periodic arrays of extended elliptical 'void-channels in PMMA, and of solid elliptical rods of cross-linked polymer in SU-8. Their lattice periods of several micrometers and typical sub-micrometric feature sizes allowed to confirm presence of pronounced photonic stop-bands at infrared wavelengths around 2.0-8.0 mum.
  • Laser Fabrication of Two-Dimensional Periodic Arrays of a TiO2-Organic Hybrid Material
    H. Segawa, S. Matsuo, H.Misawa
    Proc. XX ICG 0-11-030 2004年 [査読有り][通常論文]
  • T. Kondo, K.Yamasaki, S. Juodkazis, S. Matsuo, V.Mizeikis and H. Misawa
    Three-Dimensional Microfabrication by Femtosecon, Pulses in Dielectrics
    Thin Solid Films 453 550 - 556 2004年 [査読有り][通常論文]
  • S Juodkazis, K Yamasaki, S Matsuo, H Misawa
    APPLIED PHYSICS LETTERS 84 4 514 - 516 2004年01月 [査読有り][通常論文]
     
    We report on the use of a shape transition process to resize patterns prerecorded inside polystyrene film. The shape transition, which is shrinkage in two dimensions and expansion in the third (the volume is conserved), was brought about by annealing polystyrene above the glass transition temperature. This caused approximately twofold lateral shrinkage and fourfold axial stretching of the film, inside which micrometer-sized patterns had been recorded by femtosecond pulses. The transformation of these patterns corresponded to the macroscopic shape transformation of the film. The shape transition was also used to transform a diffraction grating. This allowed the transformation to be confirmed by the corresponding change in diffraction efficiency. The applicability of the shape transition process to nanofabrication is discussed. (C) 2004 American Institute of Physics.
  • A Takita, M Watanabe, H Yamamoto, S Matsuo, H Misawa, Y Hayasaki, N Nishida
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 43 1 168 - 171 2004年01月 [査読有り][通常論文]
     
    Optical bit recording in a human fingernail is demonstrated by using a femtosecond laser processing technique. A bit is formed in a fingernail by irradiation of a focused femtosecond laser pulse. We have investigated the dependence of the irradiation pulse energy on the diameter and length of the formed bit. The bit diameter and length are theoretically explained based on a Gaussian beam irradiation model. Furthermore, the achievable recording density is estimated from the measured bit diameter and bit length. We have found that the pulse energy required to form a bit depends on the recording depth and the surface condition of the fingernail.
  • A Transparent Microchannel Chip for Quantitative PCR
    K. Sun, Z. Li, S. Matsuo, H. Misawa
    Transactions of the Materials Research Society of Japan 29 1 339 - 342 2004年 [査読有り][通常論文]
  • Surface Plasmon Resonance Imaging Detection of DNA Hybridization Using Colloidal Au Attached Probe DNA
    M. Hayashida, H. Liu, A. Yamaguchi, S. Matsuo, H. Misawa
    Transactions of the Materials Research Society of Japan 29 1 335 - 337 2004年 [査読有り][通常論文]
  • SEET Kock Khusen, VYGANTAS Mizeikis, SAULIUS Juodkazis, 三澤 弘明
    年次大会講演論文集 2004 345 - 346 一般社団法人日本機械学会 2004年 
    The ability to construct large-scale three-dimensional microstructures efficiently and economically finds many applications in the field of MEMS, bioscience, microelectronics and optics. In photonics, 3D photonic crystals in recent years have attracted great research interests due to their novel optical properties. Fabrication of three-dimensional photonic crystals is a challenging task, as it entails microstructuring large-scale periodic structures with resolution comparable to the optical wavelength. Here we report fabrication of photonic crystals by means of direct laser writing to record extended periodic arrays of square spiral structures that are shrinkage-free and having submicrometric resolution in a commercially available negative photoresist SU-8.
  • H Takagi, K Okano, S Juodkazis, S Matsuo, H Misawa
    ADVANCED ENGINEERING MATERIALS 5 10 732 - 735 2003年10月 [査読有り][通常論文]
  • S Juodkazis, AV Rode, EG Gamaly, S Matsuo, H Misawa
    APPLIED PHYSICS B-LASERS AND OPTICS 77 2-3 361 - 368 2003年09月 [査読有り][通常論文]
     
    We report on three-dimensional (3D) optical memory recording and reading in glass by femtosecond pulses. Optically induced dielectric breakdown of glass is a mechanism of recording. The formulae of dielectric breakdown presented are applicable, in principle, for any crystalline or amorphous dielectric material. Scaling dependences of the probabilities of multi-photon and impact ionization are given. The measured threshold of an in-bulk dielectric breakdown of silica was reproduced numerically by implementing the ionization potential of Si (8.15 eV) for calculations. Exact measures of focal spot size and pulse duration at the focus allowed us to evaluate the intensity of a pulse during recording of 3D optical memory bits with high accuracy. The readout of the 3D optical memory was carried out by the white-light continuum generated from the previously damaged sites (recorded memory bits). The mechanism of the readout was a four-photon parametric interaction.
  • Mizeikis, V, S Juodkazis, JY Ye, A Rode, S Matsuo, H Misawa
    THIN SOLID FILMS 438 445 - 451 2003年08月 [査読有り][通常論文]
     
    Micromachining of silicon surface and near-surface regions by electron-beam lithography (EBL) and reactive ion dry-etching (RIE), as well as by laser microfabrication techniques is described. Combination of EBL and RIE techniques is used to fabricate quasi two-dimensional (213) photonic crystal (PhC) structures with aspect ratios at approximately 15. Structural and optical properties of PhC samples with 2D honeycomb lattice are reported, and a complete photonic band gap at wavelengths approximately 2.16 mum is identified from the optical transmission data. Next, laser microfabrication of silicon by femtosecond laser pulses is reported. Processing of silicon under low air pressure conditions (similar or equal to5 Tort) is demonstrated to be essentially debris-free process, highly suitable for cutting and scribing of wafers as well for hole drilling. Removal of thin films from the silicon surface by a single-shot laser ablation using mask projection is also demonstrated. (C) 2003 Elsevier Science B.V. All rights reserved.
  • S Tomonari, H Yoshida, M Kamakura, K Yoshida, K Kawahito, M Saitoh, H Kawada, S Juodkazis, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 42 7A 4464 - 4468 2003年07月 [査読有り][通常論文]
     
    We report on the development of a thermally isolated bimorph structure based on a Ni/Si pair. A 1-mm-long beam of the bimorph was thermally isolated by a polyimide comb from the rest of the Si structure. The Si and Ni layers of the bimorph were 20 put thick. This geometry enabled us to generate the bending displacement (the stroke) of the free end of the bimorph up to 100 mum at about 100degreesC With a generated force of about 15 mN. Electrical power consumption for the 100degreesC working point was lower than 0.2W and the response time was 0.5s. This design entitles further miniaturization of micro-electromechanical systems (MEMSs) such as commercial microvalve structures and sensors. The principles of design and experimental results of temperature distribution for the bimorph are presented and discussed.
  • S Tomonari, H Yoshida, M Kamakura, K Yoshida, K Kawahito, M Saitoh, H Kawada, S Juodkazis, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 42 7A 4593 - 4597 2003年07月 [査読有り][通常論文]
     
    We report on a new type of high-throughput thermally driven microvalve fabricated by using micro-electromechanical system (MEMS) technology. A miniaturized Si-Ni bintorph actuator was incorporated into the valve structure. This allowed the realization of both larger force generation and a longer stroke (the actuation length) combined with shortened response time. Also, a low-voltage actuation (< 3 V) and low-energy consumption (<0.2 W) were achieved. The actual size of the fabricated valve is 7.3 x 5.8 x 1.2 mm(3). The flow rate of 0 to 500 cm(3)/min at an air pressure of 47 kPa with a low leakage rate of 0.03 cm(3)/min and good linearity of air pressure control were achieved. The principles of design and experimental results on flow rate control are presented and discussed.
  • S Juodkazis, S Matsuo, N Murazawa, Hasegawa, I, H Misawa
    APPLIED PHYSICS LETTERS 82 26 4657 - 4659 2003年06月 [査読有り][通常論文]
     
    We report on the determination of the difference in the refractive index between the ordinary and extraordinary rays in droplets of nematic liquid crystal E-44 at the wavelength of laser trapping, 1064 nm. This difference was calculated by measuring the ellipticity of laser tweezers for the moment at which rotation of the trapped droplet starts. The precision of this determination of the refractive index difference is approximately 5x10(-3). Hydrophobic nematic liquid crystal E-44 formed 0.5-5-mum droplets when cast into D2O. The efficiency of the transfer of light torque to the liquid crystal droplets was determined to be 70% for the no-slip-boundary condition. (C) 2003 American Institute of Physics.
  • S Matsuo, T Fujine, K Fukuda, S Juodkazis, H Misawa
    APPLIED PHYSICS LETTERS 82 24 4283 - 4285 2003年06月 [査読有り][通常論文]
     
    The self-organization of microspheres is one of the simplest methods for fabricating three-dimensional (3D) photonic crystals (PhCs), but the 3D structure of such organized microspheres, colloidal crystals, is difficult to control. In this letter, we report a method for forming face-centered-cubic colloidal crystals into a pyramidal shape on an anisotropically etched silicon (100) and (110) substrate. The colloidal crystals were lifted from the substrate for observation after thermal bonding. Free-standing colloidal crystals with a well-defined "micropyramid" shape were obtained. This type of PhC formation is suitable for batch production as well as for handling a single pyramid. (C) 2003 American Institute of Physics.
  • Y Tanaka, A Murakami, Y Kinouchi, H Misawa
    ELECTRONICS LETTERS 39 13 1023 - 1024 2003年06月 [査読有り][通常論文]
     
    A three-dimensional (3-D) manipulation system for micro droplets generated on-demand is presented. This newly developed system using focused trapping laser beams is able to manipulate pico- to femtolitre (that is, micron-sized) droplets independently and directly. The capability of the system is demonstrated by aligning oil droplets in water. Dependence of the volume of generated droplets on some control parameters is also described.
  • T Kondo, S Matsuo, S Juodkazis, Mizeikis, V, H Misawa
    APPLIED PHYSICS LETTERS 82 17 2758 - 2760 2003年04月 [査読有り][通常論文]
     
    Femtosecond laser pulses are useful for laser microfabrication through multiphoton absorption. However, it is difficult to create interference of femtosecond pulses for the fabrication of periodic structures. In this letter, we report the fabrication of two-dimensional periodic structures by means of multibeam interference of femtosecond pulses. Scanning electron microscopy revealed a rod structure arranged into a square lattice. The possibility of controlling the period of the lattice, rod thickness, and rod shape were demonstrated. (C) 2003 American Institute of Physics.
  • E Vanagas, Kudryashov, I, D Tuzhilin, S Juodkazis, S Matsuo, H Misawa
    APPLIED PHYSICS LETTERS 82 17 2901 - 2903 2003年04月 [査読有り][通常論文]
     
    We report on a feature, that of hillock-shaped damage, formed on a glass surface by femtosecond pulses of t(p)=180 fs [full width at half maximum (FWHM) value] duration produced by a recording beam focus with energy of 5 nJ/pulse at 800 nm wavelength (the corresponding irradiance of about 7.6 TW/cm(2) was evaluated for a 0.68 mum FWHM spot size). Single hillocks of 40-50 nm height were recorded reproducibly in single-pulse irradiation. Surface nanopatterning over a large, curved area (over 200 mum(2)) can be achieved by implementing a confocal surface curvature tracking method that utilizes the reflection of a supplementary cw-laser beam. The ablation pattern achieved by this method is consistent with that of a Coulomb explosion. (C) 2003 American Institute of Physics.
  • K Yamasaki, S Juodkazis, T Lippert, M Watanabe, S Matsuo, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 76 3 325 - 329 2003年03月 [査読有り][通常論文]
     
    We report the reversible micro-structuring of a synthetic rubber polymer (cis 1,4-polybutadiene (PB)) by femtosecond laser illumination. Visco-elastic relaxation of the optically damaged region was observed. The recovery time, typically 10(2)-10(4) ms, can be varied by changing the irradiation pulse energy. Multi-shot-induced damage recovers on the much longer scale of 10(1)-10(2) s. It was found that the doping of PB by 4 wt. % of pentazadiene ([4-NO2]-phenyl-N=N-N(C3H7)-N=N-phenyl-[4-NO2]) reduces the threshold of light-induced photo-modification by 20%. This is explained by photo-induced (homolytic) cleavage of the pentazadiene bonds and formation of gaseous N-2, which facilitates material failure at the irradiated spot. The recovery of optical transmission can be applied to optical memory, optical and micro-mechanical applications. The underlying mechanism of the phenomenon is discussed in terms of anelastic alpha- and beta-relaxation (polymer backbone and chains/coils relaxation, respectively).
  • A Marcinkevicius, Mizeikis, V, S Juodkazis, S Matsuo, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 76 2 257 - 260 2003年02月 [査読有り][通常論文]
     
    We studied the peculiarities of femtosecond laser microfabrication in silica glass with a refractive index that did not exactly match the value for which the focusing optics is designed. Spherical aberrations resulting from a small refractive index mismatch were found to increase the size and distort the shape of photodamaged regions, thus reducing the spatial resolution of the microfabrication. However, these undesirable effects can be minimized, providing that the focusing depth inside the glass is not too large, and the laser intensity is kept close to the light-induced damage threshold.
  • S Juodkazis, T Kondo, Mizeikis, V, S Matsuo, H Murata, H Misawa
    PHOTON PROCESSING IN MICROELECTRONICS AND PHOTONICS II 4977 94 - 107 2003年 [査読有り][通常論文]
     
    Fabrication and characteristics of two-dimensional (2D) and three-dimensional (3D) periodic structures, recorded in the bulk of SU8 photoresist film by multiple-beam interference is described. Multiple beams (up to nine.) were generated by a diffractive beam splitter. Recording was performed by ultrashort laser pulses with temporal width of 140 fs (FVWM) and central wavelength of 800 nm, derived from a Ti:sapphire laser. Intensity-dependent photomodification of the photoresist was due to single-photon as well as multi-photon (two and three) absorption. After the development, the exposed resist films contained free-standing 2D and 3D periodic dielectric structures with unexposed exposed regions removed by the development. Detailed examination of the samples has revealed close resemblance between their structure and the light intensity distributions in the multiple-beam interference. fields, expected from the numerical calculations. Quality of the samples recorded by a single-photon absorption was lower than that of that of other samples, in particular due to poor development quality. The microfabrication method used in this work appears to be a suitable for obtaining photonic crystal templates.
  • A. Takita, H. Yamamoto, Y. Hayasaki, H. Misawa, N. Nishida
    Pacific Rim Conference on Lasers and Electro-Optics, CLEO - Technical Digest 2 691  2003年 [査読有り][通常論文]
     
    Three-dimensional optical bit recording with a femtosecond laser pulse and bit observation with atomic force microscope and fluorescence observation in human finger nail are performed. Shapes of a bit and changes of the fluorescence of nail is investigated. The bit is formed by micro-explosion and the fluorescence intensity is increased with a irradiation of a femtosecond laser pulse.
  • Electromagnetic Wave Absorption Characteristics of Light Board Made with Recycled Polyester Fiber, Magnetite and Carbon
    H. Kawai, H. Takagi, H. Misawa, Y. Kondo
    Adv. in Tech. of Mat. and Mat. Proc. J. 5 1 7 - 12 2003年 [査読有り][通常論文]
  • H Segawa, K Yoshida, T Kondo, S Matsuo, H Misawa
    JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY 26 1-3 1023 - 1027 2003年01月 [査読有り][通常論文]
     
    We report on a fabrication of photonic crystal structures in organic-inorganic hybrid films by a laser interference technique. Films containing the methacrylic group, which is photopolymerable by an adequate laser light, are prepared using a sol-gel technique from a mixture of organosilicate alkoxide and zirconium alkoxide modified by methacrylic acid. For the photopolymerization, the coated films on glass substrate are exposed to the interference light which is arranged with a square lattice in about 1 mum spacing. From microscopic images of microstructures produced by the photopolymerization, the influence of changes in conditions such as pre-bake temperature, photoinitiator and irradiation energy (laser power and duration time) on periodic structure is investigated. Adjusting the conditions, 2D and 3D photonic crystal structures with the micrometer-order period are formed in organo-silicate-zirconate hybrid materials.
  • K. Yamamoto, H. Takagi, H. Misawa, M. Morimoto
    The Japan Society of Mechanical Engineers 69 679 678 - 681 一般社団法人日本機械学会 2003年 [査読有り][通常論文]
     
    This paper deals with the recycling of bearing steel grinding swarf by high-density consolidation. The grinding swarf was compacted at the pressing pressure from 98 to 588 MPa. The maximum density of 5.41 g/cm3 was obtained at the pressing pressure of 588 MPa. Metal recovery rate that is one of the most important factors in metal recycling depended on the density of the grinding swarf briquet. The metal recovery rate of about 90% was obtained at the density of 4.8 g/cm3. Chemical compositions of original bearing steel (SUJ 2) and recycled metals obtained from melting of grinding swarf briquets in air and Ar were evaluated.
  • Laser-Asisted Microfabrication by Using Gauss-Bessel Pulses: The Evidence of Self-action
    E. Vanagas, V. Jarutis, S. Juodkazis, V. Mizeikis, I. Kudryashov, S. Matsuo, H. Misawa, R. Tomasiunas
    Lithuanian Journal of Physics 43 4 243 - 250 2003年 [査読有り][通常論文]
  • O. Efimov, S. Juodkazis, S. Matsuo, H. Misawa
    2003 European Quantum Electronics Conference, EQEC 2003 82  2003年 [査読有り][通常論文]
     
    The goal of this work is to measure the intrinsic laser-induced damage (LID) of a borosilicate glass for femtosecond pulses and to compare it with data obtained for the nanopicosecond region under conditions when self-focusing is avoided. This study demonstrates that the intrinsic LID irradiance of industrial borosilicate glass does not depend on pulse duration for 2 × 10-13 - 3 × 10-8s pulses. This finding is in favor of the LID mechanism, which is based on the phase transition scenario, rather than the currently accepted view based on a multi-photon ionization with ensuing avalanche development.
  • O. Efimov, S. Juodkazis, S. Matsuo, H. Misawa
    Conference on Lasers and Electro-Optics Europe - Technical Digest 559  2003年 [査読有り][通常論文]
     
    The goal of the present research was a study of the accumulation effect in transparent glasses and crystals under multishot irradiation by femtosecond pulses. The laser damage durability of optical components is important in the case of femtosecond pulses because of their wide application with high repetition rates for material treatments. It is concluded that, we have found existence of «cold» damage before plasma formation is reached. © 2003 IEEE.
  • OM Efimova, S Juodkazis, H Misawa
    LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 2003 5273 61 - 73 2003年 [査読有り][通常論文]
     
    This review is devoted to a long-term investigation into the nature of the laser-induced damage of silicate glasses. As an important result, we show that the threshold power density of the intrinsic damage of the boro-silicate glass at similar to1 mum wavelength does not depend on pulse duration from 2x10(-13) to 3x10(-8) s as long as self-focusing is avoided. This result cannot be explained by existing theories and indicates that the damage mechanism involves a collective response of a certain volume in the dielectric as a whole, rather than the accumulation of electrons via individual generation processes like multiphoton, tunneling, or avalanche. Special attention in the research was paid to investigation into the processes of multiple pulse damage and subthreshold modification of boro- and lead-silicate glasses.
  • H Segawa, J Tabuchi, K Yoshida, T Kondo, S Matsuo, H Misawa
    EMERGING FIELDS IN SOL-GEL SCIENCE AND TECHNOLOGY 331 - 340 2003年 [査読有り][通常論文]
     
    Photonic crystals have a periodic structure composed of two dielectric materials with different refractive indices. Recently, we produced the photonic crystal structures composed of an organic-inorganic material and air. However, the refractive index of the material was not enough high to realize the photonic band gaps. In this study, we investigate photopolymerizable organic-inorganic materials with higher refractive index for the photonic crystals. The two-dimensional photonic crystal is produced from the material using the laser interference technique.
  • JY Ye, Mizeikis, V, Y Xu, S Matsuo, H Misawa
    OPTICS COMMUNICATIONS 211 1-6 205 - 213 2002年10月 [査読有り][通常論文]
     
    We report on the fabrication and properties of quasi-two-dimensional photonic crystals (Phcs) with honeycomb lattices of dielectric rods in air. Photonic crystals, fabricated in silicon by electron beam lithography and dry-etching techniques, had the high aspect ratio of 12, corresponding to a rod height of about 7 mum. The optical transmission spectra of the samples measured in the 1.8-8 mum wavelength range, revealed pronounced features of photonic band dispersion, and a signature of a complete photonic band gap (PBG) centered at 2.3 mum wavelength. (C) 2002 Elsevier Science B.V. All rights reserved.
  • A Yamaguchi, P Jin, H Tsuchiyama, T Masuda, K Sun, S Matsuo, H Misawa
    ANALYTICA CHIMICA ACTA 468 1 143 - 152 2002年09月 [査読有り][通常論文]
     
    Applicability of polydimethylsiloxane (PDMS) for easy and rapid fabrication of enzyme sensor chips, based on electrochemical detection, is examined. The sensor chip consists of PDMS substrate with a microfluidic channel fabricated in it, and a glass substrate with enzyme-modified microelectrodes. The two substrates are clamped together between plastic plates. The sensor chip has shown no leakage around the microelectrodes under continuous solution flow (34 mul/min). Amperometric response of the sensor chips developed in this work suggest that various types of enzyme sensors can be designed by using PDMS microfluidic channels. (C) 2002 Elsevier Science B.V. All rights reserved.
  • S Juodkazis, S Matsuo, H Misawa, Mizeikis, V, A Marcinkevicius, HB Sun, Y Tokuda, M Takahashi, T Yoko, J Nishii
    APPLIED SURFACE SCIENCE 197 705 - 709 2002年09月 [査読有り][通常論文]
     
    Femtosecond laser microfabrication of 3D optical memories and photonic crystal (PhC) structures in solid glasses and liquid resins are demonstrated. The optical memories can be read out from both transmission and emission images. The PhC structures reveal clear signatures of photonic bandgap (PBG) and microcavity formation. (C) 2002 Elsevier Science B.V. All rights reserved.
  • T Takasone, S Juodkazis, Y Kawagishi, A Yamaguchi, S Matsuo, H Sakakibara, H Nakayama, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 41 5A 3015 - 3019 2002年05月 [査読有り][通常論文]
     
    Microtubules, which are flexible biopolymers, can be used for nanotechnology applications (e.g., nano-actuator) as they have a rigidity similar to that of plexyglass and other plastic materials. The flexural rigidity, or bending stiffness, of microtubules was measured using a laser trapping technique and dark-field microscopy. One end of a microtubule rod was chemically bound to a glass microsphere, while the other end was bound to a silica glass substrate. Then, the microsphere was laser-trapped and manipulated to exert three different deformation modes on the microtubule. The values of flexural rigidity for these deformations were between 10(-25) and 10(-23) Nm(2) as measured for the 5-25 mum length microtubules. The origin of the length dependence of the flexural rigidity of microtubules is discussed.
  • K Sun, A Yamaguchi, Y Ishida, S Matsuo, H Misawa
    SENSORS AND ACTUATORS B-CHEMICAL 84 2-3 283 - 289 2002年05月 [査読有り][通常論文]
     
    A microchannel chip for continuous-flow polymerase chain reaction (PCR) was developed using transparent materials. The microchannel was fabricated on a quartz glass substrate using standard photolithography and wet-etching techniques and was sealed by another quartz glass substrate. Two indium-tin-oxide (ITO) films were deposited on the etched substrate as a thermal source. To confirm the temperature distribution in the microchannel, we measured the fluorescence spectra of an aqueous solution of 1-pyrenesulfonic acid sodium salt (PS-Na), which is a temperature-indicator dye, in the microchannel under a continuous solution flow. The results confirm that the temperature distribution on the microchannel's ITO films was almost uniform (within +/-2 degreesC) under two flow rates (56 and 152 nl/min). The slightness of this deviation indicates that the ITO films integrated into the microchannel chip can be very useful as a thermal source for PCR. An amplification of a 450 bp segment of Escherichia coli HB101 was successfully per-formed by two-stage (94 and 67 degreesC) thermal cycling on the chip device. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Shigeki Matsuo, Hiroaki Misawa
    Review of Scientific Instruments 73 5 2011 - 2015 2002年05月 [査読有り][通常論文]
  • A Yamaguchi, S Juodkazis, S Matsuo, H Misawa
    CHEMISTRY LETTERS 2 190 - 191 2002年02月 [査読有り][通常論文]
     
    In this study, we demonstrate that the Au particle modified probe DNA monolayer can enhance the surface plasmon resonance (SPR) signal for measuring hybridization of unlabeled DNA molecules. The Au particles adsorbed on single stranded (ss)- and double stranded (ds)-DNA monolayers have different optical interaction with surface of Au thin film, and this difference induces the enhancement of the SPR signal.
  • S Juodkazis, K Fujiwara, T Takahashi, S Matsuo, H Misawa
    JOURNAL OF APPLIED PHYSICS 91 3 916 - 921 2002年02月 [査読有り][通常論文]
     
    We report a morphology-dependent resonance (MDR) laser emission of rhodamine-doped ellipsoidal microcavity of the poly(methylmethacrylate) particles. Elliptical particles showed different lasing properties: the lasing threshold, intramode spectral separation, mode intensity, and spectral position, when an excitation is pointed to the different locations on the particle. This differs from the well-understood MDR lasing in spherical microparticles. (C) 2002 American Institute of Physics.
  • S Matsuo, T Kondo, S Juodkazis, Mizeikis, V, H Misawa
    PHOTONIC BANDGAP MATERIALS AND DEVICES 4655 327 - 334 2002年 [査読有り][通常論文]
     
    We describe a novel microfabrication method based on interference of several coherent laser pulses in photosensitive media. The method allows to transform the periodic multidimensional interference patterns into periodic modulation of dielectric properties of the material, and is therefore potentially suitable for the photonic crystal fabrication in materials like photoresists, photosensitive glasses, and others. We have fabricated one, two, and three-dimensional photonic crystals with different lattices and sub-micrometer periods. The fabricated structures have high structural quality, as evidenced by confocal and scanning electron microscopies. Furthermore, using numerical simulations we explore the possibilities to obtain body-centered-cubic and diamond photonic crystal lattices by varying optical phases of the interfering beams. Numerical simulations are also used to reveal photonic bandgap properties of some 2D phhotonic crystals, fabricated using this technique.
  • A Yamaguchi, M Hayashida, S Juodkazis, Y Hara, S Matsuo, H Misawa
    BIOMEDICAL NANOTECHNOLOGY ARCHITECTURES AND APPLICATIONS 4626 247 - 251 2002年 [査読有り][通常論文]
     
    A probe DNA monolayer modified with Au nano-particles was prepared on an Au thin film and used for DNA hybridization detection by surface plasmon resonance (SPR) spectroscopy. This Au particle modified probe DNA monolayer resulted in about a 3.5 times larger SPR angle shift according to the hybridization reaction, compared to that found in a non-modified probe DNA monolayer. By comparison of the SPR image of the particle modified and non-modified probe DNA monolayer, this modification method was shown to be useful in improving the SPR signal for the detection of the unlabelled DNA molecules.
  • S Juodkazis, K Yamasaki, A Marcinkevicius, Mizeikis, V, S Matsuo, H Misawa, T Lippert
    MATERIALS SCIENCE OF MICROELECTROMECHANICAL SYSTEMS (MEMS) DEVICES IV 687 173 - 178 2002年 [査読有り][通常論文]
     
    We report the fabrication of complex 3D microstructures in silica and polymethylmethacrylate glass by a combination of femtosecond laser microfabrication and chemical wet etching techniques. It is demonstrated that fabrication of interconnected network of channels having lengths of about 200 mum, and diameters as small as 10 gm is possible due to the enhanced etching selectivity (typically 20 - 60) in the laser-irradiated regions. Thus, it becomes feasible to form 3D micro-fluidic and photonic crystal structures in transparent glass-like materials using this approach. In addition, preliminary results on microstructuring of rubber are presented.
  • Microfabrication of Three-Dimentional Structures in Polymer and Glass by Femtosecond Pulses
    S. Juodkazis, T. Kondo, V. Mizeikis, S. Matsuo, H. Misawa, E. Vanagas, I. Kudryashov
    Lithuania Bilateral Conference on Optoelectoronics and Magnetic Materials Proc. 2002年 [査読有り][通常論文]
  • Advantages and Short comings of Femtosecond Laser Microfabrication
    H. Misawa, S. Juodkazis, S. Matsuo, V. Mizeikis, A. Marcinkevicius
    Proc. of JUSFA 2002 2002年 [査読有り][通常論文]
  • M Watanabe, S Juodkazis, J Nishii, S Matsuo, H Misawa
    PHOTON PROCESSING IN MICROELECTRONICS AND PHOTONICS 4637 159 - 168 2002年 [査読有り][通常論文]
     
    We report the observation of 3/2-frequency generation during an Optically-induced failure of silica under femtosecond laser pulse irradiation. The origin of 3/2-frequency generation is due to a two-plasmon decay instability, which occurs at the quarter critical density of free charge carriers. We observed this emission during the optical damaging of glasses by tightly focused (numerical aperture of the objective lens was 0.5-1.35) femtosecond laser pulses. The pulse duration at the irradiation spot was about 0.35 ps, the energy 25-250 nJ, and the damage was recorded in a single shot event inside the glass. The emission at about 530 nm was only present in the spectra measured during an optical damage by 795 nm irradiation with the pulse energy 9 times and more higher than the threshold. We observed a new phenomenon applicable for microstructuring of glass. The high energy fs pulses (50-200 muJ) were focused by a plano-convex lens (focal length 2-10 cm) on the exit surface of a glass plate. The surface was ablated and the ablation was transferred into a volume of glass by translation of a "plasma spark". The length of such a channels can by up to few-cm and with a diameter of tens-of-micrometers. The mechanism and application of high-fluence fs fabrication in dielectrics is discussed.
  • S Matsuo, T Kondo, S Juodkazis, Mizeikis, V, H Misawa
    PHOTONIC BANDGAP MATERIALS AND DEVICES 4655 327 - 334 2002年 [査読有り][通常論文]
     
    We describe a novel microfabrication method based on interference of several coherent laser pulses in photosensitive media. The method allows to transform the periodic multidimensional interference patterns into periodic modulation of dielectric properties of the material, and is therefore potentially suitable for the photonic crystal fabrication in materials like photoresists, photosensitive glasses, and others. We have fabricated one, two, and three-dimensional photonic crystals with different lattices and sub-micrometer periods. The fabricated structures have high structural quality, as evidenced by confocal and scanning electron microscopies. Furthermore, using numerical simulations we explore the possibilities to obtain body-centered-cubic and diamond photonic crystal lattices by varying optical phases of the interfering beams. Numerical simulations are also used to reveal photonic bandgap properties of some 2D phhotonic crystals, fabricated using this technique.
  • The Development of Microchannel Chip Using Chemical Bonding Techniques at Room Temperature
    A. Yamaguchi, H. Tsuchiyama, S. Matsuo, J. Yokoyama, H. Misawa
    Trans. IEE of Japan 122-E 172 - 177 2002年 [査読有り][通常論文]
  • M Miwa, S Juodkazis, T Kawakami, S Matsuo, H Misawa
    APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 73 5 561 - 566 2001年11月 [査読有り][通常論文]
     
    We report herein a method for the three-dimensional (3D) fabrication of microstructures by means of direct fs-beam writing (scanning) inside a polymerizable resin. Photopolymerization takes place via two-photon absorption (TPA), as indicated by measurements of transmission power dependence. This concept of fabrication is based on two principles: the use of short, sub-picosecond pulses and simultaneous tight focusing (numerical aperture. NA > 1), This approach creates a unique opportunity for avoiding self-focusing even at very high intensities, as the power is lower than the self-focusing threshold. Under such conditions, no filament formation takes place and no thermal convection disturbance occurs in the focal vicinity during photo-polymerization. This technique requires no sacrificial layers or structures in real 3D micro-stereo-lithography.
  • Mizeikis, V, HB Sun, A Marcinkevicius, J Nishii, S Matsuo, S Juodkazis, H Misawa
    JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 145 1-2 41 - 47 2001年11月 [査読有り][通常論文]
     
    We report laser micro-fabrication of photonic crystal structures in silica glass and photopolymerizing resins, and present a detailed analysis of their structural and optical properties. Photonic crystals with 2D triangular lattice and 3D diamond lattice in glass are found to exhibit moderately pronounced photonic pseudogaps. Formation of planar microcavity is demonstrated in log-pile 3D photonic crystal, laser micro-fabricated in resin, (C) 2001 Elsevier Science B.V. All rights reserved.
  • A Marcinkevicius, S Juodkazis, S Matsuo, Mizeikis, V, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 40 11A L1197 - L1199 2001年11月 [査読有り][通常論文]
     
    We demonstrate a novel approach to femtosecond microfabrication of transparent dielectrics, which employs nondiffracting Bessel beams instead of the conventionally used Gaussian beams. The main advantage of Bessel beams is the possibility of recording linear photomodified tracks, extending along the lines of nondiffractive beam propagation without sample translation, as would be required for Gaussian beams. Recording of patterns with an aspect ratio of up to 10(2)-10(3) in vitreous silica using amplified femtosecond Ti:saphire laser pulses is demonstrated.
  • H Sugimura, T Hanji, O Takai, T Masuda, H Misawa
    ELECTROCHIMICA ACTA 47 1-2 103 - 107 2001年09月 [査読有り][通常論文]
     
    Micropatterning of organosilane self-assembled monolayers (SAMs) was demonstrated on the basis of photolithography using an excimer lamp radiating vacuum ultraviolet light of 172 nm wavelength. This lithography is generally applicable to micropatterning of organic thin films including alkylsilane SAMs, since its patterning mechanism involves cleavage of C-C bonds in organic molecules and subsequent decomposition of the molecules. In this study, SAMs were prepared on Si substrates covered with native oxide by chemical vapor deposition in which an alkylsilane, that is, octadecyltrimethoxysilane [CH3(CH2)(17)Si(OCH3)(3), ODS] was used as a precursor. SAM was photoirradiated through a photomask placed on its surface so that it was decomposed and removed in the photoirradiated area while the masked areas remained undecomposed. Accordingly, the photomask image was printed on the SAM as a removed/unremoved pattern. The patterned SAM could be used as a mask for plasma etching or area-selective Ni electroless plating. (C) 2001 Elsevier Science Ltd. All rights reserved.
  • Y Xu, HB Sun, JY Ye, S Matsuo, H Misawa
    JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS 18 8 1084 - 1091 2001年08月 [査読有り][通常論文]
     
    We report the fabrication and characterization of two-dimensional silicon-based photonic crystal (PhC) structures realized by a combination of electron-beam lithography and dry-etching techniques. PhCs of various lattices with very high aspect ratios up to 20 have been achieved, and PhC chips were prepared by standard semiconductor technologies, including thinning and cleaving. The chips consisting of high-aspect-ratio air rods or dielectric rods permit a direct transmission measurement, and they were observed to demonstrate pronounced photonic bandgap effects. Several photonic bandgap behaviors were identified by comparing transmission with reflection and experimental results with numerical results, and by considering detecting beam property. (C) 2001 Optical Society of America.
  • T Kondo, S Matsuo, S Juodkazis, H Misawa
    APPLIED PHYSICS LETTERS 79 6 725 - 727 2001年08月 [査読有り][通常論文]
     
    A simple optical interference method to fabricate microperiodic structures was demonstrated. Femtosecond laser pulse was split by a diffractive beam splitter and overlapped with two lenses. Temporal overlap of the split femtosecond pulses, which requires 10 mum order accuracy in optical path lengths, was automatically achieved by this optical setup. One-, two-, and three-dimensional periodic microstructures with micrometer-order periods were fabricated using this method. (C) 2001 American Institute of Physics.
  • P Jin, A Yamaguchi, FA Oi, S Matsuo, JB Tan, H Misawa
    ANALYTICAL SCIENCES 17 7 841 - 846 2001年07月 [査読有り][通常論文]
     
    A micro glucose sensor consisting of an interdigitated array gold microelectrode was developed. The interdigitated array structure, which has 10 mum band width and 10 mum band gap, was fabricated in a small region (2.5 x 5 mm(2)) on a quartz substrate. Glucose oxidase was chemically fixed onto the electrode surface through self-assembled monolayer of 11-mercaptoundecanoic acid; ferroceneacetic acid was used as electron mediator. Electrochemical properties of the glucose oxidase-immobilized microelectrode were investigated by cyclic voltammogram measurements. Results confirmed that the reductive ferroceneacetic acid generated at counter electrode diffuses through a narrow band gap (10 mum) and can reach the working electrode surface.
  • HB Sun, Mizeikis, V, Y Xu, S Juodkazis, JY Ye, S Matsuo, H Misawa
    APPLIED PHYSICS LETTERS 79 1 1 - 3 2001年07月 [査読有り][通常論文]
     
    We report the fabrication and characteristics of planar microcavities in a log-pile photonic crystal structure formed using light-induced photopolymerization of resin. A planar defect was introduced into the middle of the log-pile structure as a single layer with every second rod missing. The existence of confined cavity states was confirmed experimentally and by numeric simulations. The cavity resonance found at the midgap wavelength lambda (M)similar to4.0 mum had a quality factor of about 130. (C) 2001 American Institute of Physics.
  • S Juodkazis, A Yamaguchi, H Ishii, S Matsuo, H Takagi, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 40 6A 4246 - 4251 2001年06月 [査読有り][通常論文]
     
    We report the patterning of Pt on a TiO2-rutile single crystal (the fundamental absorption band starts at 396 nm) by direct deposition from a water solution of H2PtCl6 (10-20 mmol/dm(3)) using laser beam writing at 390-396 nm, or by Hg-lamp illumination (i-line at 365 nm). Pt deposition was corroborated by microchemical analysis. A resolution of the Pt patterning down to 20-30 nm was achieved. To create a Pt pattern with resolution of twenty nanometers. we employed a mask elaborated with electron-beam (EB) drawing lithography. The mask was transparent to the writing illumination. The Pt was reduced from the solution by laser beam scanning over resist-covered regions, while the pattern was formed in the openings of the resist. Separation of the growth and illumination regions, typically, by 0.5-2 mum, facilitates the deposition of reproducible, high-aspect-ratio patterns. It is demonstrated that Pt was deposited through a process of diffusion of the light-excited carriers. The possibility of fabrication of a three-dimensional Pt pattern by the overgrowth of the resist is discussed.
  • A Marcinkevicius, S Juodkazis, M Watanabe, M Miwa, S Matsuo, H Misawa, J Nishii
    OPTICS LETTERS 26 5 277 - 279 2001年03月 [査読有り][通常論文]
     
    We demonstrate direct three-dimensional (3-D) microfabrication inside a volume of silica glass. The whole fabrication process was carried out in two steps: (i) writing of the preprogrammed 3-D pattern inside silica glass by focused femtosecond (fs) laser pulses and (ii) etching of the written structure in a 5% aqueous solution of HF acid. This technique allows fabrication of 3-D channels as small as 10 mum in diameter inside the volume with any angle of interconnection and a high aspect ratio (10-mum-diameter channels in a 100-mum-thick silica slab). (C) 2001 Optical Society of America.
  • HB Sun, Y Xu, S Juodkazis, K Sun, M Watanabe, S Matsuo, H Misawa, J Nishii
    OPTICS LETTERS 26 6 325 - 327 2001年03月 [査読有り][通常論文]
     
    We used voxels of an intensely modified refractive index generated by multiphoton absorption at the focus of femtosecond laser pulses in Ge-doped silica as photonic atoms to build photonic lattices. The voxels were spatially organized in the same way as atoms arrayed in actual crystals, and a Bragg-like diffraction from the photonic atoms was evidenced by a photonic bandgap (PBG) effect Postfabrication annealing was found to be essential for reducing random scattering and therefore enhancing PEG. This technique has an intrinsic capability of individually addressing single atoms. Therefore the introduction of defect structures was much facilitated, making the technique quite appealing for photonic research and applications. (C) 2001 Optical Society of America.
  • S Juodkazis, A Marcinkevicius, M Watanabe, Mizeikis, V, S Matsuo, H Misawa
    LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 2000, PROCEEDINGS 4347 212 - 222 2001年 [査読有り][通常論文]
     
    We investigate damage of purified silica {transmission band down to 160 nm) by sub-ps light pulses having a wavelength of 795 nm. Illumination by 350 fs duration pulses focused by a high numerical aperture N A = 1.35 microscope objective results in one of the lowest reported values for the single-shot bulk light-induced damage threshold (LIDT) of 5 J/cm(2), well below the critical self-focusing power in silica. We have also investigated peculiarities of damage by two coincident laser pulses (duration 440 fs) having power of about 0.5 x LIDT, and linearly cross-polarized to avoid interference effects. The reduction of LIDT in silica is demonstrated for an elevated lattice temperature T=400 K, at which the thermal linear/volume expansion coefficient has its maximum. Comparison between the LIDT values obtained from the numeric simulation and experiments demonstrates, that the critical density of optically generated free carriers corresponding to LIDT n(cr) similar or equal to 10(21) cm(-3) is reached during the first half time of the laser pulse illumination (0.2 ps).
  • S Joko, S Komatsu, J Peng, M Shiota, F Oi, S Matsuo, H Misawa
    BIOMEDICAL INSTRUMENTATION BASED ON MICRO- AND NANOTECHNOLOGY 4265 20 - 25 2001年 [査読有り][通常論文]
     
    Self-assembled monolayers (SAMs) of alkanthiols have been studied and applied to enzyme modification on metal electrode. The construction of enzyme electrode using SAM is one of the considerable approaches for enzyme sensors. Glucose electrode and lactate electrode were fabricated on gold electrode by alkanthiols. The electrode response allowed to differentiate between long and short alkyl chains of alkantiols. This result suggests that SAM with different chain length change their surface properties and affect electrochemical response of enzyme modified electrodes. On the basis of this result, micro machined glucose electrode was fabricated and its response was measured.
  • H Misawa, S Juodkazis, A Marcinkevicius, M Watanabe, Mizeikis, V, S Matsuo
    LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING VI 4274 98 - 109 2001年 [査読有り][通常論文]
     
    We report investigation of light-induced damage threshold (LIDT) in purified silica (transmission band down to 160 nm) by 350 fs laser pulses at the wavelength of 795 nm and 498 nm. Focusing a single pulse by a high numeric aperture NA = 1.35 microscope objective lens results in one of the lowest single-shot bulk LIDT values reported so far, 5 J/cm(2), while the surface ablation threshold is 2.5 J/cm(2) with both values being well below the critical self-focusing power in silica. Furthermore, we report the peculiarities of damage by two-pulse irradiation (duration of each pulse is 440 fs), where both pulses have energies at the level of 0.5 x LIDT. Comparison between the experimental data and numeric simulation, which takes into account optical free-carrier generation and relaxation, demonstrates that these processes can explain the measured self-focusing, super-continuum generation, and light-induced damage threshold values. We argue that use of high numeric aperture objective, despite substantial temporal pulse stretching, results in tight focusing which is capable of overcoming the beam self-focusing, and the resulting fabrication quality is comparable to that obtained using shorter pulses.
  • A Marcinkevicius, S Juodkazis, Mizeikis, V, S Matsuo, H Misawa
    OPTICAL PULSE AND BEAM PROPAGATION III 4271 150 - 158 2001年 [査読有り][通常論文]
     
    We demonstrate a new technique for femtosecond microfabrication in transparent dielectrics, which employs non-diffracting Bessel-Gauss beams instead of commonly used Gaussian beams. The main advantage achieved this way is the ability to record linear photomodified tracks, extending along the line of non-diffracting beam propagation without sample translation, as would be required for Gaussian beams. The initial near infrared Gaussian laser beam was transformed into the non-diffracting Bessel-Gauss beam by a glass axicon (apex angle 160 deg). The beam was imaged into the bulk of the sample by a telescope consisting of two positive lenses, which allowed to vary the focusing cone angle from 5 degrees to 19 degrees, and maximum non-diffracting propagation distance up to 1 cm. We have recorded pre-programmed patterns of multi-shot damage tracks (diameter about 3 mum), extended uniformly along the z-axis by varying the damage spot coordinates in the x - y plane. The experiments were carried out in various transparent dielectrics: silica glass, sapphire, and plexyglass. Physical processes underlying the Gauss-Bessel microfabrication, and its potential applications for stereolithography, 3D microstructuring, and photonic crystal fabrication will be discussed.
  • A Marcinkevicius, S Juodkazis, Mizeikis, V, M Watanabe, S Matsuo, J Nishii, H Misawa
    LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING VI 4274 469 - 477 2001年 [査読有り][通常論文]
     
    We present, to the best of our knowledge, first demonstration of a direct three-dimensional (3D) microfabrication in the volume of silica glass. The microfabrication was carried out in two steps: i) recording 3-D patterns inside silica glass via silica damaging by focused femtosecond laser pulses (in multishot regime), and sample translation along X, Y, and Z directions, ii) etching the recorded patterns in HF based etchants. Comparative study of chemical etch rates in diluted HF, buffered HF, and a mixture of HF, H2O and HNO3 (P etch) reveals direct evidence of structural and/or stoichiometrical difference between damaged and "fresh" silica. 3D structures consisting of submicrometer size voxels (smallest optically damaged volume element per shot) were successfully fabricated in the silica glass. The presented technique allows fabrication of 3D channels as narrow as 10 mum inside silica, with arbitrary angle of interconnection and high aspect ratio (10 mum diameter channels in a 100 mum thick silica slab). This approach allows to speed up fabrication, and the resulting 3D structures are optically transparent, which is advantageous for optical characterization (transmission, photoluminescence, Raman scattering, etc.) with spatial resolution determined by focusing optics.
  • 三澤 弘明
    レーザー研究 29 129 - 130 The Laser Society of Japan 2001年
  • S Juodkazis, A Galeckas, J Vaitkus, S Sakai, H Misawa
    SMART OPTICAL INORGANIC STRUCTURES AND DEVICES 4318 129 - 134 2001年 [査読有り][通常論文]
     
    We have observed a apparent rotational anisotropy of the second harmonic generation (SHG) signal at lambda = 405 nm back-reflected from the surface (0001) of 3 mum-thick GaN grown by metalorganic chemical vapor deposition (MOCVD). The focusing depth of 2 mum was aimed to probe the 10-15 nm-thick buffer layer where both cubic and hexagonal phases of GaN are coexisting. Typical angular dependency clearly indicated the presence of both isotropic and sixfold contributions. The isotropic I-(2 omega)(psi) component has a minor one-fold modulation due to a ca. 2 degrees disorientation of the top surface with respect to the hexagonal planes. We attribute the substantial isotropic component to the SHG yield from the bulk of GaN. The occurrence of six-fold I-(2 omega)(psi) anisotropy, however, indicates a complementary nonlinearities, most likely due to hexagonal phase, which is coexisting with the hexagonal one in the buffer layer region. In general, both surface and bulk nonlinearities are contributing to the reflected SH yield. The symmetry of surface can differ from that in the bulk, exhibiting a corresponding angular dependence of harmonic generation. SHG mapping of GaN (0001) surface was measured from the ablated pattern. Space-Time-Spectra resolved photoluminescence (PL) was used to characterize the InGaN layers and GaN/InGaN MQW laser structures. Two-photon absorption (TPA) excited mapping of the dislocation network in GaN layers is demonstrated.
  • S Juodkazis, Mizeikis, V, K Yamasaki, M Watanabe, HB Sun, S Matsuo, H Misawa
    WORLD MULTICONFERENCE ON SYSTEMICS, CYBERNETICS AND INFORMATICS, VOL 1, PROCEEDINGS 429 - 434 2001年 [査読有り][通常論文]
     
    We report application of the laser micro-fabrication technique for realization of 3D optical memories and photonic crystals. Direct laser writing of 3D memories in the silica glass, and their readout by bright field optical imaging, light-induced defect luminescence, and white-fight continuum generation is demonstrated. Combined with a multi-foci microscopy, these techniques may allow to develop novel high-speed optical data storage systems. Direct laser writing of periodic 3D patterns in glass allows to fabricate photonic crystal structures with photonic bandgaps the near-infrared spectral region. Laser micro-fabrication and characteristics of photonic crystals in glass with 2D triangular and 3D diamond lattice types, most promising for the formation of photonic bandgaps, are reported. This technique was also used to fabricate photonic crystals with log-pile lattice in photopolymerizing resins. These structures reveal moderately pronounced photonic bandgaps, and, upon introduction of planar defects, are demonstrated to form planar microcavities with quality factors of about 130.
  • Kudryashov, I, A Gvozdev, Zhizhimontov, V, A Volkov, E Vanagas, S Juodkazis, H Misawa
    PROCEEDINGS OF THE 25TH INTERNATIONAL CONFERENCE ON THE PHYSICS OF SEMICONDUCTORS, PTS I AND II 87 1751 - 1752 2001年 [査読有り][通常論文]
     
    The mapping system, Nanofinder (R), has been developed, which allows to achieve simultaneously a high time, space and spectral resolution and allows the measurements on a single particle or region-of-interest, which is selected after a pre-scan. All this is available in real three-dimensional (3D) measurement due to confocal scheme.
  • M Watanabe, S Juodkazis, S Matsuo, J Nishii, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 39 12A 6763 - 6767 2000年12月 [査読有り][通常論文]
     
    We report the readout of three-dimensional (3-D) memory of bits from their photoluminescence (PL). The bits were recorded inside vitreous silica by optical damage (micro-explosion), which was induced by 150 fs single pulse irradiation at the focal point. The bit can be written by 0.2-0.5 muJ energy pulses at 400 nm or 800 nm (the pulse energy was given at the irradiation point and had an intensity of about 10(15) W/cm(2) when a high numerical aperture of NA = 1.3 objective lens was used for recording). The readout was obtained by the PL of the 3-D pattern of damaged bits, which were excited by quasi-continuos (repetition rate of 82 MHz) fs-irradiation at much lower pulse intensity (by a factor of 10(6)) in order to exclude secondary damage. The readout was performed by the oil-immersion objective lens of NA = 1.3. The wavelength of PL excitation was 400 nm for one-photon and 800 nm for two-photon excitation of pi, with the single pulse energy of less than 1 pJ. We found that the crosstalk of pi, readout is the same as that for the transmission imaging and measures 4 mum in the inter-plane distance for the case of one-photon excitation and can be reduced to 3 mum when a reflection-type readout system is used together with two-phr,ton excitation (theoretical axial hit size for fabrication of a given optics was 1.4 mum). Two-photon readout of 3-D memory in silica is demonstrated for the first time.
  • S Juodkazis, N Mukai, R Wakaki, A Yamaguchi, S Matsuo, H Misawa
    NATURE 408 6809 178 - 181 2000年11月 [査読有り][通常論文]
     
    Many polymer gels undergo reversible, discontinuous volume changes in response to changes in the balance between repulsive intermolecular forces that act to expand the polymer network and attractive forces that act to shrink it. Repulsive forces are usually electrostatic or hydrophobic in nature, whereas attraction is mediated by hydrogen bonding or van der Waals interactions. The competition between these counteracting forces, and hence the gel volume(1-3), can thus be controlled by subtle changes in parameters such as pH (ref. 4), temperature(5), solvent composition(6) or gel composition(7). Here we describe a more direct influence on this balance of forces, by showing that the radiation force generated by a focused laser beam induces reversible shrinkage in polymer gels. Control experiments confirm that the laser-induced volume phase transitions are due to radiation forces, rather than local heating, modifying the weak interactions in the gels, in agreement with previous observations of light-induced chain association in polymer solutions(8,9). We rnd that, owing to shear-relaxation processes(10), gel shrinkage occurs up to several tens of micrometres away from the irradiation spot, raising the prospect that the combination of stimuli-responsive polymer gels and laser light might lead to new gel-based systems for applications such as actuating or sensing.
  • T Karatsu, H Itoh, A Nishigaki, K Fukui, A Kitamura, S Matsuo, H Misawa
    JOURNAL OF PHYSICAL CHEMISTRY A 104 30 6993 - 7001 2000年08月 [査読有り][通常論文]
     
    The photochemical reactions (Z-E isomerization and photocyclization) of the s-cis and s-trans rotamers of (Z)-1-[2-(1-methryl)-2-phenylethene (Z2APE) were investigated. The absorption, steady-state and picosecond time-resolved fluorescences, and transient absorption spectra were measured in order to achieve a better understanding of the rotamer photochemistry. The spectra were compared with those of the model compounds ((Z)-1-[2-(1 -methylanthryl)]-2-phenylethene: Z1Me2APE and (Z)-1 -[2-(3-methylanthryl)]-2-phenylethene: Z3Me2APE). It is confirmed that the s-trans rotamer undergoes only Z-E adiabatic isomerization and that the s-cis rotamer mainly photocyclizes to give the dihydrophenanthrene-type intermediate with a much faster rate constant (k(cyc) = 2.3 x 10(10) s(-1).) The reason Z2APE does not give an aromatized pholocyclization product (1,2-naphtho[a]anthracene, NA) is that the return of the dihydrophenanthrene-type intermediate to the Z isomer is much faster than the oxidation to produce NA.
  • HB Sun, T Kawakami, Y Xu, JY Ye, S Matuso, H Misawa, M Miwa, R Kaneko
    OPTICS LETTERS 25 15 1110 - 1112 2000年08月 [査読有り][通常論文]
     
    Effective energy windows for two-photon absorption (TPA) photopolymerization of resins were investigated and, with a properly selected laser pulse energy, exquisite three-dimensional (3D) microstructures with submicrometer spatial resolution were achieved. The results show the inherent utility of TPA in the fabrication of real 3D patterns. In particular, we propose and utilize a resin pre-exposure technique by which freely movable components affixed to an axle are built, demonstrating a new application of TPA in laser microfabrication. (C) 2000 Optical Society of America OCIS codes: 220.3740, 220.4000, 230.4000, 160.4330, 190.4180, 160.5470.
  • K Ueno, F Kitagawa, HB Kim, T Tokunaga, S Matsuo, H Misawa, N Kitamura
    CHEMISTRY LETTERS 8 858 - 859 2000年08月 [査読有り][通常論文]
     
    A polymer microchannel (width = 100 mu m and depth = 20 mu m) chip integrated with band Au electrodes (47 x 100 mu m) was fabricated on the basis of photolithography/etching and imprinting techniques, and its characteristic electrochemical responses have been demonstrated.
  • M Watanabe, S Juodkazis, HB Sun, S Matsuo, H Misawa
    APPLIED PHYSICS LETTERS 77 1 13 - 15 2000年07月 [査読有り][通常論文]
     
    We report the readout of three-dimensional (3D) optical memory in silica by detecting the photoluminescence (PL) of the bits (voxels). A broad defect-related PL band at 400-700 nm was excited by two-photon absorption of femtosecond (pulse duration of 120 fs) illumination at 795 nm. We employed a simple reflection-type scanning readout without the use of a confocal detection scheme to read 3D memory by recording the PL of the bits (the same objective lens was used for the excitation and the collection of the PL). Bit plane separation as small as 3 mu m was resolved without cross talk, when the theoretical limit of the axial resolution evaluated as a full-width at half maximum measure of a bit size was 1.4 mu m at the fabrication conditions employed. (C) 2000 American Institute of Physics. [S0003-6951(00)00327-2].
  • HB Sun, Y Xu, JY Ye, S Matsuo, H Misawa, JF Song, GT Du, SY Liu
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 39 6B L591 - L594 2000年06月 [査読有り][通常論文]
     
    Colloidal assemblies consisting of monotonic polystyrene microspheres with a controlled degree of ordering were fabricated, and exhibited rich spectral behaviors. Smooth and spike-modulated broad attenuation regions in transmission spectra were observed in highly disordered and partly disordered samples, respectively, in contrast to the narrow peaks observed in well-ordered photonic crystals. These properties are interpreted consistently by analyzing the variation of the volume of closely packed units.
  • T Wang, T Shirahama, HB Sun, HX Wang, J Bai, S Sakai, H Misawa
    APPLIED PHYSICS LETTERS 76 16 2220 - 2222 2000年04月 [査読有り][通常論文]
     
    The influence of low-temperature buffer layer thickness on the electrical properties of GaN film is investigated, and the surface morphology is also examined by atomic force microscopy. A best surface morphology does not show best electrical properties, which could be attributed to the usual growth mechanism for GaN film on sapphire substrate. The influence of the growth temperature for the final GaN layer is also investigated. When the growth temperature increases to 1100 degrees C, the mobility is greatly enhanced to 600 cm(2)/V s with a background carrier density of 3.3x10(16)/cm(3) at room temperature. The emission energy of the near band gap exciton at a low temperature shows a blueshift with increasing growth temperature due to an enhanced thermal stress. The calculation based on a thermal stress model agrees very well with the photoluminescence measurement. This result could partly explain the reason that the previously published values for the near band gap exciton emission energy are scattered. (C) 2000 American Institute of Physics. [S0003-6951(00)02016-7].
  • HB Sun, S Juodkazis, M Watanabe, S Matsuo, H Misawa, J Nishii
    JOURNAL OF PHYSICAL CHEMISTRY B 104 15 3450 - 3455 2000年04月 [査読有り][通常論文]
     
    Properties of defects induced by irradiation with a near-infrared femtosecond laser beam into vitreous silica are reported. Three photoluminescence bands with photon energy of 1.9, 2.7, and 4.4 eV were observed under an excitation of 5.0 eV. An isochronal annealing experiment revealed that unrelaxed oxygen vacancies ODC(II) and interstitial oxygen were generated as dominant species during the irradiation. In the annealing, diffusion of the interstitial oxygen was thermally activated, leading to a direct reduction of oxygen-deficiency-related defects such as ODC(II) and E' center. The concentration of oxygen-excess-related defects such as peroxy radicals, together with nonbridging oxygen-hole centers, increased first with annealing then decreased with the exhaustion of oxygen and their precursor, the E' center. The recombination of oxygen vacancies with interstitial oxygen is characterized as the major process occurring during the annealing.
  • M Miwa, S Juodkazis, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 39 4A 1930 - 1933 2000年04月 [査読有り][通常論文]
     
    To observe hydrodynamics in microregions, we applied laser scanning manipulation to measure the drag acting on a fine glass bead moving in mineral oil sandwiched between two glass plates (the thickness of the oil layer was a 33 and 64 mu m). We measured the maximum velocity, V-M, of a laser trapped bead at which the bead was released. This allowed us to quantitatively determine the drag, the drag coefficient, C-D, and the Reynolds number, R, of the particle in the microregion of a viscous fluid. As a result, the minimum CDR was obtained midway between the two glass plates, and the CDR increased closer to the walls. Also, the distribution of CDR was in good agreement with the values calculated using the equation for wall effect in macroregions (over 0.1 mm).
  • HB Sun, JF Song, Y Xu, S Matsuo, H Misawa, GT Du, SY Liu
    JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS 17 3 476 - 480 2000年03月 [査読有り][通常論文]
     
    High-quality three-dimensional polystyrene-air photonic crystal structures with particle diameters of 200, 270, and 340 nm were grown with a quasi-equilibrium evaporation technique. The effects of the removal of interval water were evident as a blueshift of peaks, enhancement of the transmission attenuation, and changes in the gap/midgap ratio. Frequency scaling and incidence-angle-dependent transmission were also investigated; both show good agreement with the numerical simulation. (C) 2000 Optical Society of America [S0740-3224(00)01103-6] OCIS codes: 290.5850, 310.2790, 310.6860, 160.4670, 160.4760, 160.4890.
  • K Yamasaki, S Juodkazis, M Watanabe, HB Sun, S Matsuo, H Misawa
    APPLIED PHYSICS LETTERS 76 8 1000 - 1002 2000年02月 [査読有り][通常論文]
     
    We report the recording of a three-dimensional (3D) pattern in bulk polymethyl metacrylate (PMMA) films by microexplosion induced by a tightly focused (numerical aperture of oil-immersion objective was 1.3) single laser shot. Recording was done by picosecond (ps) single-pulse irradiation at 532 nm and by femtosecond at a 400 nm wavelength. The light-induced damage threshold of PMMA was found at similar to 4 MW/cm(2) for ps damaging. Readout of the 3D pattern was carried out by the recording of the transmission and the photoluminescence (PL) of bits. We demonstrate the possibility exciting PL of the optically damaged area inside the PMMA by one- and two-photon absorption. (C) 2000 American Institute of Physics. [S0003-6951(00)03208-3].
  • S Juodkazis, M Watanabe, HB Sun, S Matsuo, J Nishii, H Misawa
    APPLIED SURFACE SCIENCE 154 696 - 700 2000年02月 [査読有り][通常論文]
     
    We report the observation of photoluminescence (PL) in optically damaged vitreous silica (v-SiO2) and its gradual decrease by annealing at temperature range from room temperature to 773 K. Optical damage was induced by tightly focused picosecond or femtosecond irradiation inside v-SiO2. FL bands at 280, 470 and 650 nm were observed. The PL can be excited by 250 nm irradiation, which corresponds to the absorption band of the oxygen vacancy, V-O. The decrease of PL with annealing is explained by structural modifications of the defects in the damaged area. (C) 2000 Elsevier Science B.V. All rights reserved.
  • S Juodkazis, PG Eliseev, M Watanabe, HB Sun, S Matsuo, T Sugahara, S Sakai, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 39 2A 393 - 396 2000年02月 [査読有り][通常論文]
     
    We report experimental data on photoluminescence (PL) annealing of metalorganic chemical vapor deposition (MOCVD) grown GaN-InGaN multi quantum wells (MQWs). The formation of phase separation in the InGaN quantum well layer was confirmed by PL mapping when the MQW was grown at 675 degrees C. Spatial distribution of the yellow (Y)-band PL correlated with the dislocation network in that the intensity of the PL was lowest at the grain boundaries. The activation energy of thermal quenching of the InGaN PL at 400 nm was found to be equal to that of the increase of Y-band PL at 550 nm. The origin of the Y-band is explained as a radiative donor-acceptor recombination.
  • HB Sun, Y Xu, M Miwa, S Matsuo, H Misawa
    HIGH-POWER LASERS IN MANUFACTURING 3888 122 - 130 2000年 [査読有り][通常論文]
     
    We demonstrate in this paper a fabrication of three-dimensional microstructures using photopolymerization of resin by two-photon absorption. When a tightly focused laser beam was scanned in a light-curling liquid, solidified rods were formed following the trace of the scanning. If the solidification was arranged to occur along the frame of a microstructure, a designed spatial pattern would be transformed into material object. Due to a quadratic dependence of photopolymerization rate on the laser pulse energy, the size of solidified voxels was controlled down to submicrometer order. Infrared transmission measurement exhibited pronounced band gap effects from thus-fabricated photonic crystal structures.
  • HB Sun, S Juodkazis, PG Eliseev, T Sugahara, T Wang, S Matsuo, S Sakai, H Misawa
    HIGH-POWER LASER ABLATION II 3885 311 - 322 2000年 [査読有り][通常論文]
     
    The single-shot pulse laser-induced damaging thresholds (LIDTs), an important laser-optical constant of GaN material, were determined to approximately 34 and 65 nJ upon the irradiation of 400 and 800 nm wavelengths, 150 fs duration laser pulse focused by 40x magnification of dry objective lens (a lateral size of focal spot roughly at 1.22 lambda/NA, where NA=0.65). The critical energy of sub-threshold pulses was determined for multi-shot optical damaging. The factors that influenced the LIDTs, optical properties of damaged GaN material and the possibility of laser processing of nitride devices were also discussed.
  • HB Sun, Y Xu, S Juodkazis, K Sun, J Nishii, Y Suzuki, S Matsuo, H Misawa
    HIGH-POWER LASERS IN MANUFACTURING 3888 131 - 142 2000年 [査読有り][通常論文]
     
    We propose and utilize ultrashort laser pulses to tailor three-dimensional microstructures and their optical properties. When an intense femtosecond pulse was tightly focused into some transparent materials, a laser-induced microexplosion occurred, generating void holes inside the medium. When the thus-fabricated holes or cylinders were regularly organized, a microstructure with a periodic refractive index distribution was accomplished, which was liable to act as a photonic crystal structure. One-, two, and three-dimensional photonic lattices have been acquired by using this technique. Significant photonic band gap effects were confirmed by transmission measurements. The unique feature of the ultrashort laser micromachining of photonic crystal structures was the availability of arbitrary spatial geometry.
  • H.-B. Sun, Y. Xu, K. Sun, S. Juodkazis, J. Nishii, Y. Suzuki, S. Matsuo, H. Misawa
    Mat. Res. Soc. Symp. Proc. 605 85 - 90 2000年 [査読有り][通常論文]
     
    Ultrashort laser pulses are utilized for fabrication of three-dimensional (3D) photonic crystals based on a multiphoton absorption process. The basic idea is, when a femtosecond laser pulse is tightly focused into some transparent media, a submicrometer hole will be generated due to microexplosion. By arraying these holes the same way as atoms in general solid crystals, 3D photonic lattices are achieved. Pronounced photonic bandgap effect shows that this technique is promising for tailoring arbitrary-lattice photonic crystals.
  • H Sugimura, T Hanji, O Takai, K Fukuda, H Misawa
    MATERIALS ISSUES AND MODELING FOR DEVICE NANOFABRICATION 584 163 - 168 2000年 [査読有り][通常論文]
     
    An organic film of a few nm in thickness was applied as a resist for photolithography and scanning probe lithography. This resist film was prepared on an oxide-covered Si substrate through chemisorption and spontaneous organization of organosilane molecules, e.g., n-octadecyltrimethoxysilane. The film belongs to a class of materials referred to as self-assembled monolayer (SAM). A SAM/Si sample was irradiated through a photomask with vacuum ultraviolet (VUV) light at a wavelength of 172 nm. The photomask image was transferred to the SAM through the decomposition of the SAM. Furthermore, we demonstrate nano-scale patterning of the SAM using an atomic force microscope (AFM) with an electrically conductive probe. The SAM was electrochemically degraded in the region where the AFM probe had been scanned. Both the photo-printed and AFM-genereated patterns were successfully transferred into the Si substrates based on wet chemical etching or on dry plasma etching. At present, using these VUV and AFM-based lithographies, we have succeeded in fabricating minute features of 2 mu m and 20 nm in width, respectively.
  • H Misawa, HB Sun, S Juodkazis, M Watanabe, S Matsuo
    LASER APPLICATIONS IN MICROELECTRONIC AND OPTOELECTRONIC MANUFACTURING V 3933 246 - 260 2000年 [査読有り][通常論文]
     
    Femtosecond (fs) laser microfabrication has been gathering more research interests due to its ability to create micro- and sub-micrometer three-dimensional (3D) structures. An extremely high light intensity (-TW/cm(2)) enables multiphoton absorption (MPA) in transparent materials, upon which the spatial resolution of fabricated elements is confined to the sizes even smaller than optical diffraction limit. Our report will formulate the principles of the laser microfabrication of such applications. A direct application of single-shot pulse-induced optical damage is a 3D optical memory with a storage density of ca. 100 Gbits/cm(2) in silica. Photonic and optoelectronic applications such as optical gratings, 3D inlayed-"atom"-like and 2D cylinder-consisted photonic crystals have been fabricated in silica. Also, photopolymerization of photoresist by a scanning of focal point of laser irradiation solidifies submicrometer rods, which forms photonic lattices when packed into well-defined 3D pattern. Photonic bandgap effects (at 2-4 mu m) of above-mentioned structures were corroborated by infrared Fourier spectroscopy and numerical simulations, by which the success of laser microfabrication was evidenced. Self-focusing of fs-pulses (optical Kerr effect) is another possibility of the microstructuring of transparent materials, which is demonstrated in the case of silica. This could find its application in sub-diffraction-limited recording.
  • PG Eliseev, S Juodkazis, T Sugahara, HB Sun, S Matsuo, S Sakai, H Misawa
    HIGH-POWER LASER ABLATION III 4065 546 - 556 2000年 [査読有り][通常論文]
     
    Laser-induced ablation and surface processing are investigated in GaN epitaxial layers irradiated by 130-150 fs pulses at wavelength of 398 and 795 nm. These layers are important materials in optoelectronics and microelectronics. GaN is an inert and hard substance with very limited possibility of wet etching. Laser processing seems to be suitable for different steps of fabrication of nitride-based devices (mesa shaping, grooving, scribing, mirror and surface grating preparation, etc.). Atomic force microscopy is used for a high-resolution investigation of initial and irradiated GaN surface. Imperfections of the mirror-like as-grown (0001) surface are identified (monolayer steps, open-core dislocations). The laser-induced damage threshold (LIDT) is determined at 398 and 795 nm. The dependence of LIDT(N) on the number of shots, N, is tested in accordance with the phenomenological relation LIDT(N) = LIDT(1)N(gamma-1) in order to reveal the defects accumulation in an ablation process of GaN surface gamma = 0.86 corresponds to an accumulation-free ablation. The damage of GaN is found to be free of accumulation effect at low pulse energy below 0.6 x LIDT(1) at 795 nn and some effect is found at higher energy with gamma = 0.86 at multi-shot irradiation conditions. A successful surface processing of GaN epitaxial layer (grown by MOCVD technique) is demonstrated for a single-pulse laser ablation of a typical energy 4-6 times higher than LIDT(1). The ablation depth up to 500 nm is achievable. The edge is almost vertical and the rim of a laser-ablated channel is free of debris and peel-off. There is an experimental evidence of a successful laser processing by two-photon absorption of femtosecond pulses at GaN surface with photon energy in a transmission region of the material. Photoluminescence (PL) of the defect-related Y-band at 550-600 nm was not enhanced at the rim of ablated region when energy of ablated pulses was 3 x LIDT(1). The PL of GaN was excited by two-photon absorption of 110 +/- 10 fs illumination at 726 nm.
  • H Misawa, S Juodkazis, HB Sun, S Matsuo, JN Nishii
    1ST INTERNATIONAL SYMPOSIUM ON LASER PRECISION MICROFABRICATION 4088 29 - 32 2000年 [査読有り][通常論文]
     
    We report a novel photo-polymerization technique of well-defined three-dimensional (3D) layer-by-layer structures by two-photon absorption (TPA) in resins. By changing the structural parameters such as the rod diameter, pitch (intra-rod distance in plane) and angular orientation between neighbor planes different lattice types can be accomplished. This enables a systematic investigation of optical properties of photonic crystals (PhCs) made by TPA photo-polymerization. The solidified skeleton of PhC can be utilized as a mold to infiltrate solidifiable dye. Selective removal of the solidified resin can yield in a reverse PhC structures. When the defect-layer(s) are introduced into PhC during fabrication the PhC may act as a high-quality microcavity. A defect mode has been observed for the first time in thus-fabricated structures. Laser-microexplosion fabrication is another promising technique for the PhC and optical memory applications. To achieve an opening of a full-bandgap the media of high dielectric constant is of request (a high dielectric contrast is necessary).
  • K Yamasaki, S Juodkazis, M Watanabe, S Matsuo, K Kamada, K Ohta, H Misawa
    1ST INTERNATIONAL SYMPOSIUM ON LASER PRECISION MICROFABRICATION 4088 51 - 54 2000年 [査読有り][通常論文]
     
    We report the observation of high light-induced change in refractive index (recognizable by observation in conventional microscope) in PMMA film doped with an optically non-linear dye 2-nitroaniline (NO2(C6H4)NH2 abbreviated as 2NA). The optically altered micrometer-sized regions were fabricated by single-shot irradiation of 120 fs laser pulses into doped PMMA film using high numerical aperture 1.3 and high magnification x100 objective lens. The doping of films can be achieved in a wide range of 2NA concentrations (up to 40 wt%) without precipitation. This allows to control a storage time of an optically altered region up to one month by the adjusting the energy of the femtosecond (fs) recording pulse at 800 nm. Typical recording energy was 10-80 nJ/pulse at the point of irradiation. Total recovery of transmission of the PMMA/2NA film was confirmed by optical transmission measurements in microscope. The light induced damage threshold (LIDT) (for permanent damage) was increased more than by 4 times (up to 40 nJ/pulse) when 2NA doping were ca.13 wt%. While the LIDT for transient damage was decreased by 1.5-2 times. Total optical recovery was observed single exponential with decay time of ca. 0.5-1 min for moderate irradiation intensities (0.1xLIDT of permanent damage). The damage induced with at the higher intensities lasts up to month, but the recovery was not total (residual transmission changes were observable). The phenomenon can be applied for the optical memory, photonic crystal, and micro-mechanical applications. The underlying mechanism of the phenomenon is discussed in terms of anelastic alpha- and beta -relaxation (polymer backbone and side chain relaxation, respectively).
  • Y. Tanaka, H. Misawa, Y. Kinouchi
    T. SICE 36 5 459 - 461 The Society of Instrument and Control Engineers 2000年 [査読有り][通常論文]
     
    In this paper, a new noncontact arrangement method for metal particles is proposed. The method forms optical cages by synchronous scanning laser beams, and arranges particles in the cages. This idea, which enlarges the ability of the laser scanning manipulation, is experimentally realized.
  • Miwa Masafumi, Misawa Hiroaki, Kaneko Reizou
    IEEJ Transactions on Sensors and Micromachines 120 7 345 - 349 2000年 [査読有り][通常論文]
     
    The handling of fine structure objects consisting of micrometer-sized polystyrene latex particles by laser scanning manipulation technique using a single laser beam was demonstrated. Laser ablation technique was employed to fix polymer particles regularly aligned by laser trapping. Integrated structures created by the successive trapping/ laser ablation procedures were shown to be held by laser beam. When the trapping laser beam was scanned along the rod structure, the structure was stably held with the swinging motion of few hundreds nanometer. The swinging motion of the structure was strongly dependent on the scanning speed(Vs) of the laser beam, and swinging amplitude was reduced as Vs increased. The holding ability of the microstructure was proportional to the laser power. The present method is promising as a technique for precision holding of minute structures. © 2000, The Institute of Electrical Engineers of Japan. All rights reserved.
  • Surface Morphology of GaN Layers
    S. Juodkazis, P. Eliseev, H.-B. Sun, R. S.Q. Fareed, H. Misawa
    Lithuanian Journal of Physics 40 113 - 117 2000年 [査読有り][通常論文]
  • Photoluminescence Imaging. The Issues of Vibration Noise in Near-Field Optical Microscopy
    S. Juodkazis, M. Watanabe, H.-B. Sun, S. Matsuo, H. Misawa
    Lithuanian Journal of Physics 40 237 - 241 2000年 [査読有り][通常論文]
  • Formation of Al2O3 Based Photonic Crystals
    I. Mikulskas, S. Juodkazis, R. Tomasiunas, A. Jagminas, S. Meskinis, H. Misawa
    Lithuanian Journal of Physics 40 155 - 159 2000年 [査読有り][通常論文]
  • S Juodkazis, H Ishii, S Matsuo, H Misawa
    JOURNAL OF ELECTROANALYTICAL CHEMISTRY 473 1-2 235 - 239 1999年09月 [査読有り][通常論文]
     
    Submicrometer patterning of the TiO2-rutile single crystal surface by Pt was accomplished by means of photo-catalytic reduction of PtCl42- from aqueous solutions of H2PtCl6. The patterns of Pt were fabricated along focal point traces of a 380 nm wavelength excitation laser beam. Single particles of Pt as small as 100 nm can be grown by such techniques. (C) 1999 Elsevier Science S.A. All rights reserved.
  • HB Sun, Y Xu, S Matsuo, H Misawa
    OPTICAL REVIEW 6 5 396 - 398 1999年09月 [査読有り][通常論文]
     
    We report for the first time a laser microfabrication and its characteristics of photonic crystal structure in vitreous silica. It is two-dimensional triangle lattices composed of hollow cylinders with a periodicity of approximately 1.2 mu m. Infrared spectroscopic measurements revealed dielectric-periodicity-matched transmission valleys centering approximately at 4100 cm(-1) for H-polarization and 4000 cm(-1) for E-polarization, respectively.
  • PG Eliseev, HB Sun, S Juodkazis, T Sugahara, S Sakai, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 38 7B L839 - L841 1999年07月 [査読有り][通常論文]
     
    The laser-induced damage of epitaxially grown GaN semiconductor material is investigated for the first time by illumination of the c-plane by sub-picosecond laser pulses at the wavelength of 400 nm. The surface damage was investigated by optical and atomic force microscopies. The threshold fluence for ablation damage is determined to be similar to 5.4 J/cm(2) for pulse width of 150 fs. An application is demonstrated for laser-beam processing by the formation of clean dips on the GaN surface to depths of 240 nm in a single shot.
  • H Misawa, S Juodkazis
    PROGRESS IN POLYMER SCIENCE 24 5 665 - 697 1999年06月 [査読有り][通常論文]
     
    In this article we survey experimental results obtained by the employment of the technique called "scanning laser micromanipultion". Novel physical and chemical properties of material of micro- and sub-micrometer dimensions are elucidated by conducting experiments on an individual laser-tweezed particle. It is shown that scanning laser micromanipulation can be adopted to the particles which have a refractive index that is higher than that of the surrounding material, as well as to those which possess lower refractive index or are reflective. An implementation of this method of laser manipulation can be applied for micro-machining, optical switching and electrochemistry, as demonstrated by a series of examples. (C) 1999 Elsevier Science Ltd. All rights reserved.
  • S Juodkazis, M Shikata, T Takahashi, S Matsuo, H Misawa
    APPLIED PHYSICS LETTERS 74 24 3627 - 3629 1999年06月 [査読有り][通常論文]
     
    We demonstrate the feasibility of an all-optical liquid-crystal (LC) switch with submillisecond switching time. This switch is realized by optical manipulation of a three-dimensionally trapped microscopic nematic LC droplet using an "optical tweezers." Transmission of a polarizer/LC droplet/analyzer system can be modulated at frequencies as high as 10(3) Hz, a faster response than that of a nematic LC demonstrated so far. The response corresponds to a submillisecond switching time when the LC droplet is rotated by an angle of pi/4. The alignment of the LC droplet to the plane of the incident plane-polarized beam is also demonstrated. (c) 1999 American Institute of Physics. [S0003-6951(99)00124-2].
  • M Watanabe, S Juodkazis, HB Sun, S Matsuo, H Misawa, M Miwa, R Kaneko
    APPLIED PHYSICS LETTERS 74 26 3957 - 3959 1999年06月 [査読有り][通常論文]
     
    We demonstrate separate readouts of three-dimensional memory by (i) transmission imaging using a conventional optical microscope and (ii) photoluminescence (PL) of the bits created by inducing optical damage within the vitreous silica. Recording was done by tightly focused (objective x100, numerical aperture 1.3) single shot irradiation of 120 fs duration pulses at a 400 nm wavelength. For the readout, a broadband of PL at 470-600 nm was excited by 400 nm, 120 fs irradiation with pulse energy smaller by a factor of 10(6) compared with that for the recording. We found an erasing of the PL after 400 degrees C annealing, while the readability of the bits by the transmission was sustained. This shows the potential for two-bit information recording per single bit by means of separate readout procedures. (C) 1999 American Institute of Physics. [S0003-6951(99)05026-3].
  • S Juodkazis, M Shikata, T Takahashi, S Matsuo, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 38 5A L518 - L520 1999年05月 [査読有り][通常論文]
     
    We report the development of an all-optical liquid-crystal (LC) switch realized by laser manipulation of a three-dimensionally trapped micrometer-size nematic liquid-crystal droplet. Transmission of a polarizer/LC droplet/analyzer system can be modulated at a frequency as high as 10(3) Hz for micrometer sized LC droplets. An optical switching corresponds to the rotation of the LC droplet by an angle of pi/4. The dependence of rotation frequency on LC droplet size is explained in terms of the circularly polarized light scattering by the molecules of the LC droplet. This scattering is responsible for the transfer of angular momentum from the light to the LC droplet.
  • HB Sun, S Matsuo, H Misawa
    APPLIED PHYSICS LETTERS 74 6 786 - 788 1999年02月 [査読有り][通常論文]
     
    Three-dimensional photonic crystal structures were fabricated with laser microfabrication techniques through two-photon-absorption photopolymerization of resin. Significant band-gap effects in the infrared wavelength region were observed from "layer-by-layer'' structures. (C) 1999 American Institute of Physics. [S0003-6951(99)03506-8].
  • M Horiyama, HB Sun, M Miwa, S Matsuo, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 38 2B L212 - L215 1999年02月 [査読有り][通常論文]
     
    Three-dimensional microstructures with aspect ratios larger than 20 and a solidified wall with a thickness down to 2.0 mu m have been fabricated by the one-photon absorption photopolymerization technique. Lateral and longitudinal spatial resolutions in a single-line scanning process of as high as 1.0 mu m and 0.3 mu m, respectively, are reproducible. An experimental system consisting of a common picosecond pulsed laser and an optical microscope makes laser microfabrication easy to realize, implying a broad application potential.
  • T Takahashi, K Fujiwara, S Matsuo, H Misawa
    JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 120 2 135 - 140 1999年01月 [査読有り][通常論文]
     
    Energy transfer from excited state donor to ground state acceptor dyes in polymer microparticles with a diameter of 30-60 mu m was observed under lasing condition. The energy transfer efficiency was found to be higher with the increasing size of the particle. This result indicates that the excitation energy transfer efficiency can be controlled by the particle size without varying temperature and dye concentration. The dynamics of energy transfer was observed through picosecond time-resolved emission spectral measurements. (C) 1999 Elsevier Science S.A. All rights reserved.
  • Suzuki, I, R Tanaka, A Yamaguchi, S Maki, H Misawa, K Tokumaru, R Nakagaki, H Sakuragi
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 72 1 103 - 113 1999年01月 [査読有り][通常論文]
     
    The reaction course of acyl-diphenylmethyl biradicals (alpha-oxo-omega, omega-diphenyl-alpha, omega-alkanediyl biradicals), O=C-up arrow-(CH2)(n-2)-(CPh2)-Ph-up arrow ((BR)-B-3-n), generated from the Norrish type-I reaction of 2,2-diphenylcycloalkanones (CK-n) with various ring sizes in methanol, is switched from intramolecular disproportionation (n = 6, 7), giving a diphenylalkenal, to acylphenyl recombination (n greater than or equal to 9), affording a cyclophane derivative. The behavior of (BR)-B-3-9 derived from CK-9 was studied in detail; the photolysis of CK-9 afforded an open-chain and a cyclic decarbonylation product together with an unsaturated aldehyde and a 4-methylene-2,5-cyclohexadienyl ketone (a pre-cyclophane). The photolysis of this ketone gave the same products that arose from the photolysis of CK-9, presenting the possibility that the decarbonylation products and a part of the aldehyde are formed as secondary products during irradiation. The magnetic field dependence of the lifetimes of (BR)-B-3-n (n = 12 and 13) generated from CK-12 and 13, respectively, was measured in methanol by means of a pulsed-laser excitation technique. The rate constants for intersystem crossing showed a maximum at a relatively low field strength, which decreased with increasing the field strength to level off to an asymptotic value at > 1.5 kG. The results show that the role of hyperfine coupling in intersystem crossing is less important in these systems, presumably because of the presence of a carbonyl oxygen and the absence of a hydrogen atom at the radical center.
  • T. Takahashi, S. Matsuo, H. Misawa, T. Karatsu, A. Kitamura, K. Kamada, K. Ohta
    Nonlinear Optics 22 1-4 397 - 400 1999年 [査読有り][通常論文]
     
    Laser oscillation phenomena in dye-doped microspheres of some organic polymers were investigated. In case of poly(cyclohexylmethylsilane) (PCHMSi) microspheres, a spectral shift in lasing wavelengths was observed with increasing pumping power. The shift was explained in terms of optical Kerr effect (OKE) which come from the lasing light. The effective electric field which induced the OKE was estimated; the value was larger than that of pumping laser light. This result indicates that the effective electric field of light was efficiently amplified inside the microspheres.
  • M. Watanabe, H.-B. Sun, S. Juodkazis, S. Matsuo, H. Misawa
    Phys. Rev. B 60 14 9959 - 9964 1999年 [査読有り][通常論文]
  • M Watanabe, HB Sun, S Juodkazis, T Takahashi, S Matsuo, Y Suzuki, J Nishii, H Misawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 37 12B L1527 - L1530 1998年12月 [査読有り][通常論文]
     
    To achieve high bit densities (>10 GB/cm(3)) in optical memory, we accomplished a three-dimensional optical data storage system using vitreous silica as the recording material. We succeeded in high-density optical recording by focusing pulsed laser beams of 532 nm (full width at half maximum [FWHM] 30 ps) and 400 nm (150 fs). A recording density of 72.9 GB/cm(3) was achieved, which corresponded to that of 100 compact disks, on a glass plate of (2 x 2) cm(2) and 2.2 mm thickness. We found that the optical damage of silica occurs within 400 ps after irradiation by a single pulse for 30 ps at 532 nm. Three photoluminescence bands were found in the photomodified silica at 283 nm, 468 nm and 558 nm. All the three bands showed similar photoluminescence excitation spectra, i.e. a peak related to oxygen vacancy absorption at 250 nm.
  • T Takahashi, S Matsuo, H Misawa, T Karatsu, A Kitamura, K Kamada, K Ohta
    THIN SOLID FILMS 331 1-2 298 - 302 1998年10月 [査読有り][通常論文]
     
    Laser oscillation from dye-doped microparticles of organic polymers was investigated. Spectral shift in peak wavelengths of laser oscillation depending on pumping intensity was observed in the microparticles of poly(cyclohexylmethylsilane) (PCHMSi). The shift observed for PCHMSi microparticles was discussed in terms of the third-order non-linear optical (NLO) effect. It was concluded that the effective power density of light just inside the microparticle's surface was about 30 times larger than that of the pump pulse. (C) 1998 Elsevier Science S,A, All rights reserved.
  • H Ishii, S Juodkazis, S Matsuo, H Misawa
    CHEMISTRY LETTERS 7 655 - 656 1998年07月 [査読有り][通常論文]
     
    Submicrometer patterning of TiO2-rutile single crystal surface by Pt was accomplished by means of photocatalytic reduction of PtCl42- to Pt in an aqueous solution of H2PtCl6. The patterns of Pt were fabricated along focal point traces of 380 nm wavelength excitation laser beam on the surface of rutile substrates.
  • M Ishikawa, H Misawa, N Kitamura, R Fujisawa, H Masuhara
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 69 1 59 - 66 1996年01月 [査読有り][通常論文]
     
    The phase transition of an aqueous poly(N-isopropylacrylamide) solution (PNIPAM, wt% = 1.8-3.6%) was induced by the irradiation of a focused (ca. 1 mu m) 1064-nM laser beam; this brought about the formation of a single PNIPAM microparticle. The diameter of the particle was controlled to 2-9 mu m through the laser power, polymer concentration, and solution temperature. The primary origin of particle formation was the photo-thermal phase transition of the polymer solution through the local heating of water (H2O) by the laser beam. The characteristic features of the phenomena, including manipulation of the PNIPAM particle by the incident laser beam and the role of radiation force for the particle formation, are discussed.
  • M Ishikawa, H Misawa, N Kitamura, M Irie, H Masuhara
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 68 12 3397 - 3402 1995年12月 [査読有り][通常論文]
     
    Photostimulated volume expansion of polyacrylamide microgels (initial radius=11-235 mu m) bearing triphenylmethyl cyanide moieties (AAm-TPMCN) in water was studied on the basis of simultaneous measurements of the degree of ionic dissociation (alpha) of TPMCN to TPM(+) (triphenylmethyl cation) and the gel radius. The time profile of the radius change, r(t), was analyzed by a convolution relation between r(t) and the time course of alpha (alpha(t)). The characteristic time constants of the volume change, related to the cooperative diffusion coefficient of the gel network, were determined for AAm-TPMCN gels with various radii. The faster photoresponse time of the volume change for the smaller AAm-TPMCN gel was explained in terms of the diffusion theory of gel networks in water.
  • T Araki, H Misawa
    REVIEW OF SCIENTIFIC INSTRUMENTS 66 12 5469 - 5472 1995年12月 [査読有り][通常論文]
     
    A compact pulsed-light source is devised from an InGaN/AlGaN double heterostructure light-emitting diode (LED). The LED emits a 450-nm (blue) light under conventional de operation below 30 mA. When a current larger than 50 mA is applied, the intensity of the 450-nm Light saturates, but that of the 380-nm light due to the InGaN component continues to increase. This phenomenon is utilized to realize a nanosecond ultraviolet (UV) light source. Under repetitive, large current pulsing (frequency=10 kHz, pulse width=4 ns, peak current=2 A), the peak LED emission shifts from 450 to 380 nm. Intense light pulses (peak value=40 mW) of 4-ns duration were generated. To evaluate the potential of the pulsed LED as an excitation source, the fluorescence lifetime of a quinine-sulfate solution was measured. The observed Lifetime characteristics agreed well with the generally accepted behavior. (C) 1995 American Institute of Physics.
  • S FUNAKURA, K NAKATANI, H MISAWA, N KITAMURA, H MASUHARA
    JOURNAL OF PHYSICAL CHEMISTRY 99 41 15192 - 15197 1995年10月 [査読有り][通常論文]
     
    Transient absorption microspectroscopy tvas developed for studies on photophysical and photochemical processes in a single laser-manipulated microdroplet in water. Transient absorption spectra and their decay curves of individual tri-n-butyl phosphate (TBP) microdroplets containing zinc tetraphenylporphyrin (ZnTPP) were measured and analyzed. Owing to the intense laser excitation, the concentration of the ZnTPP triplet state was so high that the decay profiles of T-n <-- T-l absorbance of ZnTPP obeyed the second-order kinetics, triplet-triplet (T-T) annihilation. Simultaneously the delayed fluorescence of ZnTPP was observed and analyzed in terms of T-T annihilation. The estimated rate constant of T-T annihilation (k(TT)) was comparable to that obtained from Tn <-- T-l absorption spectroscopy. Assuming the T-T annihilation is diffusion-controlled, the inner viscosity of a single TBP microdroplet was obtained and examined as a function of the diameter of the microdroplets. A remarkable micrometer size effect that the inner viscosity is decreased with the droplet diameter was found and discussed in terms of a swollen TBP droplet owing to the penetration of water.
  • M TAJIMA, H MISAWA, H INOUE
    JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 89 1 53 - 59 1995年06月 [査読有り][通常論文]
     
    The photochromic behaviour of 1-(2-naphthoxy)anthraquinone (1) was investigated using electronic spectroscopy and kinetic analysis of the decay of coloured species. The decay of coloured species well obeyed first-order kinetics and consisted of two processes, reversion to the starting substance and the change toward final formation of 1-hydroxyanthraquinone (2). The reversion process was revealed to proceed through two different pathways having activation enthalpies of 30.5 and 104 kJ mol-1. The lower value suggests that the reversion proceeds from a rotational isomer of 1 while the higher value comes from a structural isomer of 1, 9-naphthoxy-1,10-anthraquinone. The activation enthalpy of the change toward final formation of 2 was 49.1 kJ mol(-1). The possible formation of the two different coloured species from the two conformers of 1 on light irradiation was discussed.
  • A Biological-sensor Utilizing a Living Cell for Environment Monitoring in Micro Space
    T. Araki, H. Misawa, K. chikamori, Y. Tohno
    Proc. The International Symposium on Microsystems 301 - 304 1995年 [査読有り][通常論文]
  • Laser Manipulation Technique and Its Role in Study of Micromachine
    M. Miwa, H. Misawa, T. Araki, T. Yoshimura
    Proc. The International Symposium on Microsystems 67 - 70 1995年 [査読有り][通常論文]
  • U PFEIFERFUKUMURA, H MISAWA, H FUKUMURA, H MASUHARA
    CHEMISTRY LETTERS 9 1589 - 1592 1994年09月 [査読有り][通常論文]
     
    Polystyrene microspheres were modified with polar and nonpolar groups. A fluorescent probe with spectral properties sensitive to environments was used to characterize the surface. Using the technique of laser trapping the fluorescence spectrum of the dye could be observed from a single particle dispersed in solution.
  • K NAKATANI, T UCHIDA, H MISAWA, N KITAMURA, H MASUHARA
    JOURNAL OF ELECTROANALYTICAL CHEMISTRY 367 1-2 109 - 114 1994年04月 [査読有り][通常論文]
     
    The electrochemistry of ferrocene (FeCp) in a single micrometer-sized nitrobenzene droplet dispersed in water was studied by laser trapping and microelectrochemical techniques. Mass transfer of FeCp, ferrocenium ion, and tetra-n-butylammonium ion between the droplet and water phases accompanied by oxidation of FeCp proceeded across the droplet\water interface. The peak potential of a cyclic voltammogram of FeCp was highly dependent on the potential sweep rate. The potential shift was analyzed by thin-layer electrolysis and the results are discussed in terms of the irreversible electron transfer of FeCp across the droplet\electrode interface and in terms of mass transfer of ion species across the droplet\water interface.
  • S FUNAKURA, K NAKATANI, H MISAWA, N KITAMURA, H MASUHARA
    JOURNAL OF PHYSICAL CHEMISTRY 98 12 3073 - 3075 1994年03月 [査読有り][通常論文]
     
    An absorption microspectroscopy system was developed for absorption measurements of a laser-manipulated individual microdroplet in water under an optical microscope. Absorption spectra of various sizes of individual tri-n-butyl phosphate (TBP) microdroplets containing zinc tetraphenylporphyrin (ZnTPP) were studied as a model. Absorbance of ZnTPP in the droplet was confirmed to increase linearly with the diameter of the droplet, showing that the Lambert-Beer law is followed for droplets with a diameter larger than 6 mum. The concentration of ZnTPP in the droplet dispersed in water is lower than that for pure TBP film by a fixed proportion, which was considered in terms of a constant water partition into TBP.
  • K SASAKI, H MISAWA
    MICROCHEMISTRY 30 5B 23 - 34 1994年 [査読有り][通常論文]
  • T KARATSU, H MISAWA, M NOJIRI, N NAKAHIGASHI, S WATANABE, A KITAMURA, T ARAI, H SAKURAGI, K TOKUMARU
    JOURNAL OF PHYSICAL CHEMISTRY 98 2 508 - 512 1994年01月 [査読有り][通常論文]
     
    Deuterated ethenylanthracenes, 1-, 2-, and 9-(ethenyl-(Z)-2-d)anthracene, and 2-(ethenyl-(E)-2-d)anthracene ((Z)-1-, 2-, and 9-EAD, and (E)-2-EAD, respectively) undergo photochemical Z-E isomerization under thermal activation. The temperature dependence of their isomerization quantum yields and the temperature independence of lifetimes of their T-n <-- T-1 absorptions indicate that EADs isomerize adiabatically between the Z and E isomers in the lowest excited triplet state by overcoming an activation barrier (E(a) = 19-46 kJ mol(-1)) of the perpendicularly twisted geometry. The activation parameters of isomerization, Delta H double dagger (17-42 kJ mol(-1)) and Delta S double dagger (-40 to -113 J K-1 mol(-1)), decrease in the order of 2-, 1-, and 9-isomers; however, Delta G double dagger (50-54 kJ mol(-1)) is almost constant irrespective of the substitution position of the anthracene nucleus.
  • H MISAWA, K SASAKI
    MICROCHEMISTRY 49 - 64 1994年 [査読有り][通常論文]
  • K KAMADA, K SASAKI, R FUJISAWA, H MISAWA
    MICROCHEMISTRY 287 - 300 1994年 [査読有り][通常論文]
  • N KITAMURA, K SASAKI, H MISAWA, H MASUHARA
    MICROCHEMISTRY 35 - 48 1994年 [査読有り][通常論文]
  • K SASAKI, H MISAWA, N KITAMURA, R FUJISAWA, H MASUHARA
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS 32 8B L1144 - L1147 1993年08月 [査読有り][通常論文]
     
    Optical manipulation of a lasing microparticle in water was demonstrated. A rhodamine B-doped poly(methyl methacrylate) particle was simultaneously manipulated and pumped by 1064 nm CW and 532 nm pulsed Nd3+:YAG laser beams, respectively. Optical interactions between lasing and closely positioned nonlasing particles were studied by a multibeam laser micromanipulation technique.
  • K KAMADA, K SASAKI, H MISAWA, N KITAMURA, H MASUHARA
    CHEMICAL PHYSICS LETTERS 210 1-3 89 - 93 1993年07月 [査読有り][通常論文]
     
    Lasing of a dye-doped polymer microparticle in water was induced with the 532 nm ps pulse excitation from a Q-switched Nd3+:YAG laser. Temporal characteristics of the laser oscillation was confirmed in a few tens of ps time region, which depends on both wavelength and dye concentration. The lasing dynamics was interpreted in terms of quality factors (Qs) of the lasing cavity due to absorption by dye.
  • H MISAWA, R FUJISAWA, K SASAKI, N KITAMURA, H MASUHARA
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 32 6A L788 - L790 1993年06月 [査読有り][通常論文]
     
    Simultaneous optical manipulation and lasing of a rhodamine 640-doped polystyrene latex particle in water was demonstrated through irradiation of a single focused 1064 nm CW Nd:YAG laser beam. Lasing of the particle resulting from two-photon absorption was confirmed from periodically spaced peaks in the emission spectrum and from nonlinear (more than quadratic) dependence of the emission intensity upon the incident laser power.
  • K NAKATANI, T UCHIDA, H MISAWA, N KITAMURA, H MASUHARA
    JOURNAL OF PHYSICAL CHEMISTRY 97 20 5197 - 5199 1993年05月 [査読有り][通常論文]
     
    Electrochemical behavior of ferrocene (FeCp) in a single tri-n-butyl phosphate microdroplet (diameter = approximately 20 mum) dispersed in water was studied by a new method of laser trapping-electrochemistry-spectroscopy. Mass transfer of FeCp and ferrocenium ion (FeCp+) across the droplet-water interface accompanied by electrolysis of FeCp in the droplet was directly measured and analyzed. The results were discussed in terms of a distribution reequilibrium of FeCp across the interface, which was spectroscopically supported by fluorescence quenching of 9,10-diphenylanthracene by FeCp in the droplet.
  • K NAKATANI, T UCHIDA, S FUNAKURA, A SEKIGUCHI, H MISAWA, N KITAMURA, H MASUHARA
    CHEMISTRY LETTERS 4 717 - 720 1993年04月 [査読有り][通常論文]
     
    A dye formation reaction between 4-N,N-diethyl-2-methylquinonediimine and a phenol derivative at the oil-droplet/water interface was studied by a microelectrochemical method combined with laser trapping of an individual droplet in an oil-in-water emulsion system. The reaction in a single droplet with almost-equal-to 10 mum diameter was shown to be controlled by the distance between the droplet and a microelectrode.
  • M ISHIKAWA, H MISAWA, N KITAMURA, H MASUHARA
    CHEMISTRY LETTERS 3 481 - 484 1993年03月 [査読有り][通常論文]
     
    Irradiation of a focused 1064 nm laser beam to an aqueous poly(N-isopropylacrylamide) solution resulted in the reversible microparticle (diameter almost-equal-to 7 mum) formation through local heating of water by the laser beam and subsequent phase transition of the polymer solution. The microparticle produced was simultaneously manipulated in three-dimensional space by the incident 1064 nm laser beam.
  • K NAKATANI, H MISAWA, K SASAKI, N KITAMURA, H MASUHARA
    JOURNAL OF PHYSICAL CHEMISTRY 97 8 1701 - 1706 1993年02月 [査読有り][通常論文]
     
    Pyrene excimer formation in individual liquid paraffin droplets dispersed in aqueous gelatin matrices was studied by three-dimensional space- and time-resolved fluorescence spectroscopy. The pyrene excimer formation efficiency in the droplets was constant irrespective of the droplet size. The parameters of the excimer formation were determined for each droplet and compared with those observed in bulk pyrene/liquid paraffin solution. The results were discussed on the basis of the depth profiles and the dynamics of pyrene fluorescence in individual liquid paraffin droplets. A distribution equilibrium of pyrene between the oil and the aqueous gelatin was also considered.
  • H MISAWA, K SASAKI, M KOSHIOKA, N KITAMURA, H MASUHARA
    MACROMOLECULES 26 2 282 - 286 1993年01月 [査読有り][通常論文]
     
    Three-dimensional laser manipulation of polymer latex particles in solution was demonstrated. Polymer latex particles with a diameter of several microns were spatially aligned in arbitrary patterns (letters and geometrical figures) by repetitively scanning a focused laser beam (1064 nm) under an optical microscope. Irradiation of nanosecond or picosecond 355-nm laser pulses on individual laser-trapped polymer particles in a sample solution containing polymerizable vinyl monomers and a photoinitiator brought about permanent fixation of the particles in three-dimensional structures. Possible roles of the laser trapping/manipulation techniques in studying the chemistry and physics of polymeric microparticles are also discussed.
  • R. Tanaka, I. Suzuki, A. Yamaguchi, H. Misawa, H. Sakuragi, K. Tokumaru
    Tetrahedron Lett. 33 25 3651 - 3654 1992年06月 [査読有り][通常論文]
     
    The reaction course of biradicals, O=C up-(CH2)n-2-C up Ph2, generated from Norrish type I reaction of 2,2-diphenylcycloalkanones with various ring sizes, is switched from intramolecular disproportionation (n=6, 7) to acyl-phenyl recombination (n greater-than-or-equal-to 9) in methanol.
  • U PFEIFER, H FUKUMURA, H MISAWA, N KITAMURA, H MASUHARA
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 114 11 4417 - 4418 1992年05月 [査読有り][通常論文]
  • M KOSHIOKA, H MISAWA, K SASAKI, N KITAMURA, H MASUHARA
    JOURNAL OF PHYSICAL CHEMISTRY 96 7 2909 - 2914 1992年04月 [査読有り][通常論文]
     
    Fluorescence characteristics of a single microcapsule containing a toluene solution of pyrene were studied by three-dimensional space- and time-resolved fluorescence spectroscopy. Although pyrene excimer formation dynamics observed for the microcapsules by spatially-unresolved spectroscopy did not obey simple excimer formation kinetics (i.e., Birks kinetic model), that for a single microcapsule measured by spatially-resolved spectroscopy was shown to be described by the Birks kinetics model. The efficiency and dynamics of the excimer formation in individual capsules were different between the capsules owing to the concentration distribution of pyrene in the capsules. The importance of dynamic fluorescence spectroscopy for an individual small particle is discussed.
  • H MASUHARA, N KITAMURA, H MISAWA, K SASAKI, M KOSHIOKA
    JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 65 1-2 235 - 247 1992年04月 [査読有り][通常論文]
     
    The importance of micrometre dimensions in photochemistry is considered, and a systematic study on laser spectroscopy and photochemistry in small micrometre volumes is reported. To measure chemical reactions in the small volumes, submicrometre space- and picosecond time-resolved fluorescence and transient absorption spectroscopy was developed by employing a confocal laser scanning microscope. Laser-trapping phenomena were used for choosing small (micrometre-sized) materials as well as reagents, transferring them to a certain position with micrometre resolution and inducing chemical reactions. Combined with spectroscopic analysis, the laser-trapping technique was developed as a laser manipulation-spectroscopy-reaction method. Utilizing these methods, characteristic micrometre-sized effects were confirmed in the excimer dynamics in microdroplets and photoresponse of gels. Some small (micrometre-sized) reaction fields, which are crucial for conducting chemical reactions, were created by microfabrication techniques. Summarizing our trials, our goal to create an integrated chemical system named microphotoconversion is presented.
  • M ISHIKAWA, H MISAWA, N KITAMURA, M IRIE, H MASUHARA
    CHEMISTRY LETTERS 2 311 - 314 1992年02月 [査読有り][通常論文]
     
    The dynamics of photostimulated volume expansion of a polyacrylamide microgel containing triphenylmethane leucocyanide (TPMCN) in water was studied by simultaneous measurements of the time response of absorbance of triphenylmethyl cation (Abs(t)) and the radius of the gel (R(t)). The time response of the degree of ionic dissociation of TPMCN (alpha(t)) in the gel was obtained by analyzing Abs(t) and R(t) for the first time. The change in R(t) was shown to be slower than that in alpha(t).
  • K SASAKI, M KOSHIOKA, H MISAWA, N KITAMURA, H MASUHARA
    APPLIED PHYSICS LETTERS 60 7 807 - 809 1992年02月 [査読有り][通常論文]
     
    Laser trapping of a metal particle in water or a water droplet in liquid paraffin, which cannot be attained by irradiation of a TEM00 mode focused laser beam, was experimentally confirmed based on a scanning laser trapping technique. Although a metal particle or a water droplet experiences repulsive radiation force from a laser beam (1064 nm, focused into a approximately 1-mu-m spot), scanning of the laser beam circularly around the particle was successful to optically trap and tweezer the particle. Water and ethylene glycol droplets dispersed in liquid paraffin were also shown to be manipulated independently by scanning double laser-beam trapping.
  • Laser Manipulation and Ablation of a Single Polymer Microsphere in Solution
    H. Masuhara, N. Kitamura, H. Misawa
    Proc. LAMP ’92, Nagaoka 1023 - 1028 1992年 [査読有り][通常論文]
  • Three-Demensional Laser Manipulation of Microspheres and Its Role in Micromachining
    N. Kitamura, H. Misawa, K. Sasaki, H. Masuhara
    Proc.THE FIRST INTERNATIONAL CONFERENCE ON INTELLIGENT MATERIALS 267 - 270 1992年 [査読有り][通常論文]
  • H MISAWA, K SASAKI, M KOSHIOKA, N KITAMURA, H MASUHARA
    APPLIED PHYSICS LETTERS 60 3 310 - 312 1992年01月 [査読有り][通常論文]
     
    A multibeam laser trapping-reaction system was developed to demonstrate independent manipulation of plural microparticles as well as to induce photochemical reaction in a laser-trapped particle(s). Photopolymerization of vinyl monomers dissolved in a sample solution was employed to fix polystyrene latex particles regularly aligned by laser trapping. Integrated latex structures created by the successive manipulation/polymerization procedures were also shown to be freely manipulated by laser beams.
  • S. Konuma, S. Aihara, Y. Kuriyama, H. Misawa, R. Akaba, H. Sakuragi, K. Tokumaru
    Chem. Lett. 11 1897 - 1900 1991年11月 [査読有り][通常論文]
     
    Pulsed laser excitation studies on the reactive species in 9-cyanoanthracene(CNA)-sensitized oxygenation of 1,1-diphenyl-2-methylpropene (1a) and (E)-2,3-diphenyl-2-butene (1b) show that the reaction course is mostly governed by competitive quenching of the CNA excited singlet by 1 and oxygen to produce 1+. and 1O2, respectively. The results indicate that the reaction courses of tetraphenylethylene and 2,3-dimethyl-2-butene, for example, can be explained by exclusive quenching of sensitizer singlets by the olefin and oxygen, respectively.
  • H MISAWA, N KITAMURA, H MASUHARA
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 113 21 7859 - 7863 1991年10月 [査読有り][通常論文]
     
    Laser manipulation and ablation of a single microcapsule containing a pyrene/toluene solution were demonstrated for the first time. Irradiation of an individual capsule by a focused (approximately 1-mu-m) laser beam from a CW Nd3+:YAG laser (1064 nm) enabled us three-dimensional optical manipulation of the capsule in water. When a laser-trapped microcapsule was further irradiated by a 355-nm laser pulse (pulse width approximately 7 ns), deformation or ablative decomposition of the capsule was observed depending on the pulsed-laser intensity. The pyrene/toluene droplet ejected from the capsule upon laser ablation was shown to be tweezered by the 1064-nm laser beam. Spectroscopic characterization of individual capsules and droplets was achieved by a laser trapping-spectroscopy technique. Ablation mechanism was also discussed in terms of the pyrene concentration dependence of the ablation threshold energy.
  • H MISAWA, M KOSHIOKA, K SASAKI, N KITAMURA, H MASUHARA
    JOURNAL OF APPLIED PHYSICS 70 7 3829 - 3836 1991年10月 [査読有り][通常論文]
     
    We developed a laser trapping-ablation system comprised of CW and pulsed Nd3+:YAG lasers as well as of an optical microscope. Three-dimensional manipulation of various kinds of particles and laser ablation of a single optically trapped, poly(methyl methacrylate) latex particle in water were demonstrated. A minute hole with its diameter of approximately sub-mu-m was fabricated on the latex particle (approximately 6-mu-m diameter). The hole size produced was much smaller than the effective diameter of the excitation laser beam, suggesting nonlinear optical (self-focusing of the laser beam) and photochemical (multiphoton absorption) mechanisms for the present laser trapping ablation. Characteristic features of the laser trapping-ablation are discussed in detail.
  • K SASAKI, M KOSHIOKA, H MISAWA, N KITAMURA, H MASUHARA
    OPTICS LETTERS 16 19 1463 - 1465 1991年10月 [査読有り][通常論文]
     
    A novel micromanipulation technique is proposed for aligning fine particles on micrometer-scale spatial patterns and for moving the particles continuously along the formed patterns. This technique is based on the repetitive scanning of a focused trapping laser beam. The velocity of the particle flow can be controlled by scan speed and laser power. The origin of the driving force is considered theoretically and experimentally.
  • H MISAWA, M KOSHIOKA, K SASAKI, N KITAMURA, H MASUHARA
    CHEMISTRY LETTERS 3 469 - 472 1991年03月 [査読有り][通常論文]
     
    Polystyrene latex particles with the diameter of almost-equal-to 1-mu-m in water were laser trapped in spatial images of a laser beam. For a mixture of latex particles with different diameters, delicate tuning of the images resulted in size selection of the particles. Directional flow of the particles in water was also achieved by laser irradiation.
  • Y TAKEDA, S TAKAHARA, Y KOBAYASHI, H MISAWA, H SAKURAGI, K TOKUMARU
    CHEMISTRY LETTERS 11 2103 - 2106 1990年11月 [査読有り][通常論文]
  • H MISAWA, M KOSHIOKA, K SASAKI, N KITAMURA, H MASUHARA
    CHEMISTRY LETTERS 8 1479 - 1482 1990年08月 [査読有り][通常論文]
  • L BONAZZOLA, JP MICHAUT, J RONCIN, H MISAWA, H SAKURAGI, K TOKUMARU
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 63 2 347 - 352 1990年02月 [査読有り][通常論文]
  • Y NISHIMURA, H MISAWA, H SAKURAGI, K TOKUMARU
    CHEMISTRY LETTERS 9 1555 - 1558 1989年09月 [査読有り][通常論文]
  • Y TAKEDA, H MISAWA, H SAKURAGI, K TOKUMARU
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 62 7 2213 - 2218 1989年07月 [査読有り][通常論文]
  • S YAMAUCHI, N HIROTA, S TAKAHARA, H MISAWA, K SAWABE, H SAKURAGI, K TOKUMARU
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 111 12 4402 - 4407 1989年06月 [査読有り][通常論文]
  • T ARAI, T KARATSU, H MISAWA, Y KURIYAMA, H OKAMOTO, T HIRESAKI, H FURUUCHI, H ZENG, H SAKURAGI, K TOKUMARU
    PURE AND APPLIED CHEMISTRY 60 7 989 - 998 1988年07月 [査読有り][通常論文]
  • H MISAWA, T KARATSU, T ARAI, H SAKURAGI, K TOKUMARU
    CHEMICAL PHYSICS LETTERS 146 5 405 - 409 1988年05月 [査読有り][通常論文]
  • H MISAWA, K SAWABE, S TAKAHARA, H SAKURAGI, K TOKUMARU
    CHEMISTRY LETTERS 2 357 - 360 1988年02月 [査読有り][通常論文]
  • RA CALDWELL, H MISAWA, EF HEALY, MJS DEWAR
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 109 22 6869 - 6870 1987年10月 [査読有り][通常論文]
  • Y USUI, H MISAWA, H SAKURAGI, K TOKUMARU
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 60 5 1573 - 1578 1987年05月 [査読有り][通常論文]
  • Y USUI, H MISAWA, H SAKURAGI, K TOKUMARU
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 60 5 1573 - 1578 1987年05月 [査読有り][通常論文]
  • JL GOODMAN, KS PETERS, H MISAWA, RA CALDWELL
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 108 21 6803 - 6805 1986年10月 [査読有り][通常論文]
  • H MISAWA, A WAKISAKA, H SAKURAGI, K TOKUMARU
    CHEMISTRY LETTERS 3 293 - 294 1985年 [査読有り][通常論文]
  • A WAKISAKA, H MISAWA, H SAKURAGI, K TOKUMARU
    CHEMISTRY LETTERS 3 295 - 296 1985年 [査読有り][通常論文]
  • H MISAWA, A KITAMURA, H SAKURAGI, K TOKUMARU
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 57 4 1167 - 1168 1984年 [査読有り][通常論文]
  • H MISAWA, T KANNO, H SAKURAGI, K TOKUMARU
    DENKI KAGAKU 51 1 81 - 82 1983年 [査読有り][通常論文]
  • H MISAWA, H SAKURAGI, Y USUI, K TOKUMARU
    CHEMISTRY LETTERS 7 1021 - 1024 1983年 [査読有り][通常論文]
  • Y SHIMAMURA, H MISAWA, T OGUCHI, T KANNO, H SAKURAGI, K TOKUMARU
    CHEMISTRY LETTERS 11 1691 - 1694 1983年 [査読有り][通常論文]

講演・口頭発表等

  • Plasmon-induced artificial photosynthesis systems  [招待講演]
    三澤 弘明
    Tsukuba nano MA 2015 (Satellite symposium of NIMS conference) 2015年07月 口頭発表(招待・特別)
  • Plasmon-induced Artificial Photosynthesis  [招待講演]
    三澤 弘明
    27th International Conference on Photochemistry (ICP2015) 2015年06月 口頭発表(招待・特別)
  • プラズモニック化学の新展開 −プラズモンによる物理過程の増強から化学過程の増強に向けて−  [招待講演]
    三澤 弘明
    第8回プラズモニック化学シンポジウム 2015年06月 公開講演,セミナー,チュートリアル,講習,講義等
  • Plasmon-induced Artificial Photosynthesis  [招待講演]
    三澤 弘明
    CFP/NIM Workshop on Functional Photonics and Nanosystems 2015年05月 口頭発表(基調)
  • 全可視光の利用を可能にするプラズモン人工光合成の構築  [招待講演]
    三澤 弘明
    日本化学会第95春季年会(ATP企画「資源・次世代エネルギーと環境->太陽エネルギー変換の新技術と展望」) 2015年03月 口頭発表(招待・特別)
  • 空中窒素の光固定  [招待講演]
    三澤 弘明
    日本化学会第95春季年会(中長期企画「水素社会と人工光合成」) 2015年03月 口頭発表(招待・特別)
  • Plasmon-Induced Artificial Photosynthesis  [招待講演]
    三澤 弘明
    The 1st Joint Workshop between Istitute of Physics (IOP), Academia Sinica & Research Institute for Electronic Science (RIES), Hokkaido University 2015年03月 口頭発表(招待・特別)
  • Plasmon-induced artificial photosynthesis systems  [招待講演]
    三澤 弘明
    5th Symposium on “Application of Light and Materials for the Innovation of Technology and Life 2015年03月 口頭発表(招待・特別)
  • プラズモニック化学を利用する光エネルギー変換システム  [招待講演]
    三澤 弘明
    第21回バイオテンプレート研究懇談会 2015年03月 口頭発表(招待・特別)
  • 局在プラズモンを用いた太陽光エネルギー変換システムの開拓  [招待講演]
    三澤 弘明
    平成26年度日本表面科学会東北・北海道支部講演会 2015年03月 口頭発表(招待・特別)
  • Plasmon-induced Artificial Photosynthesis  [招待講演]
    三澤 弘明
    18th Osaka City University International Conference 2015年03月 口頭発表(基調)
  • Plasmon-induced Artificial Photosynthesis Systems  [招待講演]
    三澤 弘明
    RCAS and Research Institute for Electronic Science (RIES), Hokkaido University Workshop 2014年12月 口頭発表(招待・特別)
  • Frontier in Plasmonic Chemistry  [招待講演]
    三澤 弘明
    國立交通大學應用化學系103學年度第一學期専題演講 2014年12月 公開講演,セミナー,チュートリアル,講習,講義等
  • Plasmon-induced Artificial Photosynthesis Systems  [招待講演]
    三澤 弘明
    2014 International Conference on Artificial Photosynthesis 2014年11月 口頭発表(招待・特別)
  • Plasmon-induced Artificial Photosynthesis Systems  [招待講演]
    三澤 弘明
    8th Asian Photochemistry Conference 2014年11月 口頭発表(招待・特別)
  • Plasmon-induced Water Splitting System  [招待講演]
    三澤 弘明
    The 2014 ECS and SMEQ Joint International Meeting 2014年10月 口頭発表(招待・特別)
  • Plasmon-induced artificial photosynthesis systems  [招待講演]
    三澤 弘明
    15th Chitose International Forum on Photonics Science & Technology 2014年10月 口頭発表(招待・特別)
  • Plasmon-induced solar energy conversion systems  [招待講演]
    三澤 弘明
    The 6th IEEE international Nanoelectronics Conference 2014 2014年07月 口頭発表(招待・特別)
  • Plasmon-induced Water Splitting System  [招待講演]
    三澤 弘明
    The XXVth IUPAC Symposium on Photochemistry 2014年07月 口頭発表(招待・特別)
  • Plasmon-Induced Water Splitting  [招待講演]
    三澤 弘明
    Do we need a global project on artificial photosynthesis (solar fuels and chemicals)? (Theo Murphy Scientific Discussion Meeting) 2014年07月 口頭発表(招待・特別)
  • Plasmon-induced Water Splitting System  [招待講演]
    三澤 弘明
    Light Conference-International Conference on Micro/Nano Optical Engineering (ICOME2014) 2014年07月 口頭発表(招待・特別)
  • Plasmon-induced Water Splitting System  [招待講演]
    三澤 弘明
    2nd International Workshop on Ultrafast Laser Optoeletronics 2014年07月 口頭発表(招待・特別)
  • Towards nanostructure-enhanced photoenergy conversion in the plasmonic chemical reaction field  [招待講演]
    三澤 弘明
    Collaborative Conference on Materials Research 2014年06月 口頭発表(招待・特別)
  • Visible Plasmon-Enhanced Water Splitting  [招待講演]
    三澤 弘明
    225th ECS Meeting 2014年05月 口頭発表(招待・特別)
  • Towards nanostructure-enhanced photoenergy conversion in the plasmonic chemical reaction field  [招待講演]
    三澤 弘明
    IEEE The 3rd International Symposium on Next-Generation Electronics 2014年05月 公開講演,セミナー,チュートリアル,講習,講義等
  • プラズモンを利用した可視・近赤外光による人工光合成系の構築  [招待講演]
    三澤 弘明
    日本化学会第94春季年会 2014年03月 口頭発表(招待・特別)
  • プラズモニック化学の将来展望  [招待講演]
    三澤 弘明
    さきがけ「光の利用と物質材料・生命機能」平成25年度研究報告会 2014年03月 口頭発表(招待・特別)
  • Future perspective of plasmonic chemistry  [招待講演]
    三澤 弘明
    Symposium on Functional Nanostructures (Symposium Honoring the 60th Birthday of Prof. Thomas W. Ebbesen) 2014年01月 シンポジウム・ワークショップパネル(指名)
  • Future Perspective of Plasmonic Chemistry  [招待講演]
    MISAWA Hiroaki
    Seminar (Academia Sinica) 2014年01月 公開講演,セミナー,チュートリアル,講習,講義等
  • プラズモニック化学の将来展望  [招待講演]
    三澤 弘明
    CREST「元素戦略を基軸とする物質・材料の革新的機能の創出」『安定な有機ラジカルの蓄電および光電変換材料への応用』チーム会議 2014年01月 口頭発表(招待・特別)
  • 可視光局在プラズモンの人工光合成への展開  [招待講演]
    三澤 弘明
    文部科学省私立大学戦略的研究基盤掲載支援事業「太陽光活用を基盤とするグリーン/ライフイノベーション創出技術研究拠点の形成」第2回公開発表会 2013年11月 口頭発表(招待・特別)
  • プラズモニック光化学:人工光合成・太陽電池への展開  [招待講演]
    三澤 弘明
    JST・CREST「元素戦略」領域H25全体会議 2013年09月 その他
  • プラズモニック化学:人工光合成・太陽電池への展開  [招待講演]
    三澤 弘明
    2013年光化学討論会(特別講演賞受賞講演) 2013年09月 口頭発表(招待・特別)
  • Towards nanostructure-enhanced photoenergy conversion in the plasmonic chemical reaction filed  [招待講演]
    三澤 弘明
    International Photochemistry Conference 2013 2013年07月 口頭発表(基調)
  • Plasmon-enhanced photocurrent generation and water oxidation  [通常講演]
    三澤 弘明
    Symposium on Plasmon-based Chemistry and Physics (Pre-conference of ICP2013) 2013年07月 シンポジウム・ワークショップパネル(指名)
  • Plasmon-Enhanced Photocurrent Generation and Water Oxidation (Workshop)  [招待講演]
    三澤 弘明
    The 2nd International Summer Course and Workshop on "Single Molecule/Nanoparticle Spectroscopy and Imaging" 2013年06月 シンポジウム・ワークショップパネル(指名)
  • Fabrication and characterization of metal nanostructures (Summer Course)  [招待講演]
    三澤 弘明
    The 2nd International Summer Course and Workshop on "Single Molecule/Nanoparticle Spectroscopy and Imaging" 2013年06月 公開講演,セミナー,チュートリアル,講習,講義等
  • プラズモニック化学 ー反応制御を目指してー  [招待講演]
    三澤 弘明
    第10回日本写真学会光機能材料セミナー ー光励起制御を目指した金属ナノ構造の構築ー 2013年06月 公開講演,セミナー,チュートリアル,講習,講義等
  • 近赤外光を如何にして利用するか?  [招待講演]
    三澤 弘明
    日本化学会第93春季年会 2013年03月 口頭発表(招待・特別) 立命館大学、草津
  • プラズモニック光電変換と次世代人工光合成  [招待講演]
    三澤 弘明
    日本化学会第93春季年会 2013年03月 口頭発表(招待・特別) 立命館大学、草津
  • 局在プラズモンを用いた光電変換システムの構築とその人工光合成系への展開  [招待講演]
    三澤 弘明
    第13回先端フォトンテクノロジー研究センターシンポジウム 2013年03月 口頭発表(招待・特別) 名古屋 豊田工業大学
  • プラズモニック化学の新展開  [招待講演]
    三澤 弘明
    第3回電磁メタマテリアル講演会 2013年02月 公開講演,セミナー,チュートリアル,講習,講義等
  • Plasmon-Assisted Photocurrent Generation and Water Oxidation  [招待講演]
    三澤 弘明
    Physics Colloquium, Konstanz University 2013年01月 公開講演,セミナー,チュートリアル,講習,講義等 Konstanz University
  • プラズモニック光電変換システムとその人工光合成系への展開  [招待講演]
    三澤 弘明
    日本学術振興会アモルファス・ナノ材料第147委員会第118回研究会 2012年12月 口頭発表(招待・特別)
  • Near-Infrared Plasmon-Assisted Water Oxidation  [招待講演]
    Hiroaki Misawa
    South China University of Technology 2012年11月 公開講演,セミナー,チュートリアル,講習,講義等 South China University of Technology, Guangzhou, China
  • Near-Infrared Plasmon-Assisted Water Oxidation  [招待講演]
    Hiroaki Misawa
    7th Asian Photochemistry Conference 2012(APC 2012) 2012年11月 口頭発表(招待・特別) Osaka University, Osaka, Japan
  • Plasmon-Assisted Photocurrent Generation and Water Oxidation  [招待講演]
    Hiroaki Misawa
    2012 RCAS-TNNA Symposium 国際検討会 Recent Development in Nanomaterials: Structures, Dynamics & Applications 2012年10月 口頭発表(基調) Academia Sinica, Taipei, Taiwan
  • Plasmon-Assisted Photocurrent Generation Systems  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Xu Shi, Kei Murakoshi, Haruo Inoue
    IUMRS-ICEM 2012 2012年09月 口頭発表(招待・特別) Pacifico Yokohama, Yokohama, Japan
  • 局在プラズモンによる光電変換  [通常講演]
    三澤 弘明, 石旭, 孫泉, 小竹勇己, 上野貢生
    2012光化学討論会 2012年09月 口頭発表(一般)
  • Plasmon-Assisted Photocurrent Generation and Water Oxidation  [招待講演]
    Hiroaki Misawa
    The Opening Ceremony of NICE2 and Forum on Environment Nanotechnology 2012年08月 公開講演,セミナー,チュートリアル,講習,講義等 Harbin Institute of Technology, Harbin, China
  • Plasmon-Assisted Photocurrent Generation and Water Oxidation  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Xu Shi, Kei Murakoshi, Hauro Inoue
    Collaborative Conference on Materials Research (CCMR) 2012 2012年06月 口頭発表(招待・特別) Seoul Palace, Seoul, Korea
  • Near-Infrared Plasmonic-Assisted Water Oxidation on Gold Nanostructured TiO2 Photoelectrodes  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Kei Murakoshi, Haruo Inoue
    International Conference on Materials, Energy and Environment (ICMEE) 2012年05月 口頭発表(招待・特別) Park Inn Hotel Toledo, Toledo, U.S.A.
  • Plasmon-Enhanced Water Oxidation on Gold Nanostructured TiO2 Single Crystal Substrates  [招待講演]
    Hiroaki Misawa, Yoshiaki Nisijima, Kosei Ueno, Kei Murakoshi, Haruo Inoue
    Nanostructures for Energy Conversion Symposium, 221th Meeting of the Electrochemical Society 2012年05月 口頭発表(招待・特別) Washington State Convention Center, Seattle U.S. A
  • 透明材料表面に形成したプラズモニックナノ構造の光科学とその光エネルギー変換への展開  [招待講演]
    三澤 弘明
    講演会 2012年04月 公開講演,セミナー,チュートリアル,講習,講義等 横浜 旭硝子中央研究所
  • プラズモニック太陽光エネルギー変換システムの構築  [招待講演]
    三澤 弘明
    日本化学会第92春季年会シンポジウム「プラズモニック化学の新展開」 2012年03月 公開講演,セミナー,チュートリアル,講習,講義等 慶應義塾大学日吉キャンパス、横浜
  • 近赤外プラズモンを用いた光電変換システム・人工光合成系の構築  [招待講演]
    三澤 弘明
    第4回フォトニックデバイス・応用技術研究会 2012年01月 公開講演,セミナー,チュートリアル,講習,講義等 古河電気工業株式会社横浜研究所、横浜
  • Plasmon-assisted Water Oxidation on Gold Nanostructured TiO2 Single Crystal Substrates  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Kei Murakoshi, Haruo Inoue
    3rd International Forum on Photoenergy Future (IFPF) 2011年12月 口頭発表(招待・特別) Ramada Plaza Jeju, Jeju Island, Korea
  • Near-Infrared Plasmon-assisted Water Oxidation on Gold Nanostructured TiO2 Photoelectrodes  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Kei Murakoshi, Haruo Inoue
    2011 RCAS-ANNA国際検討会, Studies of Nano and Bio-Materials using Laser, X-ray and Single-Molecule Techniques 2011年11月 口頭発表(招待・特別) Academia SInica, Taipei, Taiwan
  • 局在プラズモンを利用した光化学反応  [招待講演]
    三澤 弘明
    第7回励起ナノプロセス研究会 2011年11月 口頭発表(招待・特別) ビッグ・アイ 国際障害者交流センター、堺市
  • Plasmon-enhanced Water Oxidation on Gold Nanostructured TiO2 Photoelectrodes  [招待講演]
    MISAWA Hiroaki
    Internationl Workshop on Quantum Manipulation of Atoms and Photons 2011年10月 口頭発表(基調) Jin Sha Hotel, Shanghai, China
  • Plasmon-assisted Water Oxidation on Gold Nanostructured TiO2 Photoelectrodes  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Youzhuan Zhang, Kosei Ueno, Kei Murakoshi, Haruo Inoue
    CeNS Workshop 2011 “Nanosciences: From molecular systems to functional materials” 2011年09月 口頭発表(招待・特別) the Venice International University, Venice, Italy
  • Plasmon-assisted Water Oxidation on Gold Nanostructured TiO2 Photoelectrodes  [通常講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Youzhuan Zhang, Kosei Ueno, Kei Murakoshi, Haruo Inoue
    XXV International Conference on Photochemistry (ICP 2011) 2011年08月 口頭発表(一般) Beijing Friendship Hotel, Beijing, China
  • Plasmon-assisted Photocurrent Generation Using an Au-nanorods/TiO2 Electrode  [招待講演]
    Hiroaki Misawa, Kosei Ueno, Yoshiaki Nishijima, Yukie Yokota
    International Conference on Materials for Advanced Technologies, Symposium EE: CGCT-5-Functional Materials Crystallization, Characterization and Devices 2011年06月 口頭発表(招待・特別) Suntec Singapore and the Pan Pacific Singapore Hotel, Singapore
  • Plasmon-Assisted Photocurrent Generation  [招待講演]
    Hiroaki Misawa, Kosei Ueno, Yoshiaki Nishijima, Yukie Yokota, Kei Murakoshi
    International WWorkshop on Nanoplasmonics for Energy and the Environment 2011年06月 口頭発表(招待・特別) Hotel Carlos I, Sanxenxo, Spain
  • プラズモン増強光化学反応  [招待講演]
    三澤 弘明
    ナノ学会第9回大会 2011年06月 口頭発表(招待・特別) 北海道大学、札幌
  • Electromagnetic Field Enhancement Effects on Surface-enhanced Raman Scattering Using Nano-engineered Gold Particles  [招待講演]
    Hiroaki Misawa, Yukie Yokota, Kosei Ueno
    IUPAC International Congress on Analytical Sciences 2011 2011年05月 口頭発表(招待・特別) Kyoto International Conference Center, Kyoto
  • Plasmon-Assisted Photocurrent Generation System  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Yukie Yokota, Kei Murakoshi
    The 5th International Conference on Surface Plasmon Photonics 2011年05月 口頭発表(招待・特別) BEXCO, Busan, Korea
  • プラズモニクス研究の新展開ー発光増強や光電変換への応用ー  [招待講演]
    三澤 弘明
    講演会 2011年04月 口頭発表(招待・特別) 横浜 旭硝子中央研究所
  • Photochemical reactions on nano-engineered gold particles  [通常講演]
    Hiroaki Misawa, Kosei Ueno, Naoki Murazawa, Yoshiaki Nishijima, Yukie Yokota, Kei Murakoshi
    Pacifichem 2010 “The Nanostructure-Enhanced Photochemical Reactions” 2010年12月 口頭発表(一般) Sheraton Waikiki, Honolulu, Hawaii, USA
  • Plasmon-Assisted Photocurrent Generation System  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Yukie Yokota, Kei Murakoshi
    The 4th GCOE International Symposium: Towards a Sustainable Future 2010年11月 口頭発表(招待・特別) Hokkaido University, Sapporo
  • 見えない光、赤外線を利用する太陽電池  [招待講演]
    三澤 弘明
    学術講演会『北海道から発信するグリーンイノベーション』 2010年11月 公開講演,セミナー,チュートリアル,講習,講義等 北海道大学、札幌
  • 局在プラズモンによる新しい励起プロセスを用いた光化学反応  [招待講演]
    三澤 弘明
    【光化学基礎講座12】光化学の基礎概念と実験技術講座 2010 2010年11月 口頭発表(招待・特別) 大阪大学、大阪 光化学協会
  • Plasmon-Enhanced Photochemical Reactions  [招待講演]
    Hiroaki Misawa
    Korea Nano Optical Society 2010 (KNOS 2010) 2010年08月 口頭発表(基調) KINTEX, Ilsan Gyeonggido
  • Plasmon-Assisted Photocurrent Generation from Visible to Near-Infrared Wavelength Using an AU-Nanorods/TiO2 Electrode  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Yukie Yokota, Kei Murakoshi
    Korea-Japan Joint Forum 2010 on Organic Materials for Electronics and Photonics (KJF2010) 2010年08月 口頭発表(招待・特別) Kitakyushu International Conference Center, Kitakyushu, Fukuoka
  • Plasmon Assisted Photocurrent Generation System from Ultraviolet to Near-infrared Wavelength  [通常講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Yukie Yokota, Kei Murakoshi
    18th International Conference on Photochemical Conversion and Storage of Solar Energy (IPS-18) 2010年07月 口頭発表(一般) Korea University, Seoul, Korea
  • 光と物質の新しい相互作用−光−分子強結合反応場の創成ー  [招待講演]
    三澤 弘明
    講演会 2010年07月 口頭発表(招待・特別) 富士フイルム㈱先端コア技術研究所、開成町、神奈川県 富士フイルム株式会社
  • フェムト秒レーザーによる3次元加工  [招待講演]
    三澤 弘明
    日本光学会(応用物理学会)光波シンセシス研究グループ主催第17回研究会「光波シンセシスとトポロジー理工学」 2010年07月 公開講演,セミナー,チュートリアル,講習,講義等 北海道大学、札幌
  • Plasmon-Assisted Photocurrent Generation System from Visible to Near-infrared Wavelength  [通常講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Yukie Yokota, Kei Murakoshi
    XXIII IUPAC Symposium on Photochemistry 2010年07月 口頭発表(一般) Polo Didattico degli Adelardi, Ferrara, Italy
  • Plasmon Assisted Photochemistry  [招待講演]
    Hiroaki Misawa
    講演 2010年06月 公開講演,セミナー,チュートリアル,講習,講義等 East China Normal University, Shanghai, China
  • Photochemistry on Nanoengineered Gold Structures  [招待講演]
    Hiroaki Misawa, Kosei Ueno, Yoshiaki Nishijima, Yukie Yokota
    The International Conference on Nanophotonics 2010 2010年06月 口頭発表(招待・特別) Epocal Tsukuba, Tsukuba
  • Nanoparticle Plasmon-assisted Photochemical Reactions  [招待講演]
    Hiroaki Misawa, Kosei Ueno, Naoki Murazawa, Yukie Yokota
    The Nanostructures for Energy Conversion Symposium, 217th Meeting of Electrochemical Society 2010年04月 口頭発表(招待・特別) The Hyatt Regency Vancouver, Canada
  • Gold Nano-sturcture Enhanced Photocurent Generation System from Ultraviolet to Near-infrared Wavelength  [招待講演]
    Hiroaki Misawa, Yoshiaki Nishijima, Kosei Ueno, Yukie Yokota, Kei Murakoshi
    International Symposium on Chemical Conversion of Light Energy 2010年03月 口頭発表(招待・特別) Kinki University, Higashi-Osaka
  • Gold Nano-Structure Enhanced Photocurrent Generation System from Ultraviolet to Infrared Wavelength  [招待講演]
    Hiroaki Misawa
    3rd Taiwan-Japan Joint Symposium on Organized Nanomaterials and Nanostructures Related to Photoscience 2010年03月 口頭発表(招待・特別) Grand Formosa Taroko Hotel, Taroko National Park, Hualien, Taiwan
  • 光ナノアンテナによる広波長帯域太陽光エネルギー変換システムの開発  [招待講演]
    三澤 弘明
    京都・先端ナノテク総合支援ネットワーク 第8回ナノテクシンポジウム「フォトニクス研究の推進とナノテクノロジー支援の可能性」 2010年03月 口頭発表(招待・特別) ホテル日航奈良、奈良
  • イントロダクトリートーク:光ー分子強結合反応場の創成に向けて  [招待講演]
    三澤 弘明
    第57回応用物理学関連連合講演会 2010年03月 口頭発表(招待・特別) 東海大学、平塚
  • Gold Nano-Structure Enhanced Photocurrent Generation System from Ultraviolet to Near-Infrared Wavelength  [招待講演]
    Hiroaki Misawa
    JAPAN NANO 2010 2010年02月 口頭発表(招待・特別) Tokyo BIg Sight, Tokyo
  • Nanoparticle Plasmon-assisted Photochemical Reactions  [招待講演]
    Hiroaki Misawa
    Invited seminar 2009年12月 公開講演,セミナー,チュートリアル,講習,講義等 CNRS et Universite de Strasbourg, France
  • Photophysical and Photochemical Process on Nanoengineered Gold Structures  [招待講演]
    Hiroaki Misawa
    Optics and Photonics Taiwan 2009 (OPT 2009) 2009年12月 口頭発表(招待・特別) Taiwan Normal University, Taipei
  • 光ナノアンテナによるナノ空間における反応と計測  [招待講演]
    三澤 弘明
    MNC 2009 技術セミナー 2009年11月 口頭発表(招待・特別) シェラトン札幌、札幌
  • Nanoparticle plasmon-assisted photochemical reactions  [通常講演]
    Hiroaki Misawa
    Wazapolooza 2009 (Micheal R. Wasielewski’s 60th Birthday Celebration) 2009年09月 ポスター発表 Northwestern University, Evanston, U.S.A.
  • フェムト秒レーザーリソグラフィの開発とその3次元フォトニック結晶加工への応用  [招待講演]
    三澤 弘明
    第58回高分子討論会 2009年09月 口頭発表(招待・特別) 熊本大学、熊本
  • 金属ナノ構造形成とプラズモン共鳴  [招待講演]
    三澤 弘明
    日本分光学会第45回夏期セミナー「表面プラズモンを利用した高感度表面・界面分光の基礎原理と測定手法を学ぶ」,「顕微分光法ーナノ・マイクロの世界をみる分光法」,「NMR分光法」 2009年09月 口頭発表(招待・特別) 幕張メッセ国際会議場、千葉
  • 電気泳動チップを用いた核酸・タンパク質の新規分主装置の開発  [招待講演]
    三澤 弘明
    第3回次世代医療システム産業化フォーラム2009 2009年06月 公開講演,セミナー,チュートリアル,講習,講義等 大阪商工会議所、大阪
  • 金属ナノ構造による光の捕集・局在とその光化学反応場への展開  [通常講演]
    三澤 弘明
    国際高等研究所 研究プロジェクト「ナノ物質量子相の科学」2009年度第1回研究会 2009年06月 口頭発表(招待・特別) 国際高等研究所、木津川
  • Photochemical reactions on gold nanoparticles  [招待講演]
    三澤 弘明
    215th ECS Meeting 2009年05月 口頭発表(招待・特別) San Francisco Hilton, San Francisco
  • フォトンのハンドリングと光化学への展開  [招待講演]
    三澤 弘明
    先端光機能材料の創発に関する光化学シンポジウムー徳丸克己先生退官15周年を記念してー 2009年05月 口頭発表(招待・特別) 学士会館、東京
  • Photochemistry on Nano-engineered Au Structures  [招待講演]
    Hiroaki Misawa
    The Second International Symposium on Interdisciplinary Materials Science(ISIMS-2009) 2009年03月 口頭発表(招待・特別) Tsukuba International Congress Center, Tsukuba
  • Non-Linear Photochemical Reactions on Nano-Engineered Gold Nanoparticles  [招待講演]
    Hiroaki Misawa
    Asian Academic Seminar 2009 2009年03月 口頭発表(招待・特別) KSP Hall, Kanagawa
  • 光ナノアンテナの構造設計とSERSへの展開  [招待講演]
    三澤 弘明
    日本分光学会 高感度表面・界面分光部会第1回シンポジウム 2008年12月 口頭発表(招待・特別) 産業技術総合研究所つくばセンター、つくば
  • Non-linear Photochemical Reactions Induced in the Near-field Region of Sub-wavelength Optical Antennae under Incoherent Excitation  [招待講演]
    Hiroaki Misawa
    The 2nd Japan-Taiwan Joint Symposium on Organized Nanomaterials and Nanostructures Related to Photoscience 2008年11月 口頭発表(招待・特別) Kyoto University Clock Tower Centennial Hall, Kyoto
  • Photochemistry on Nano-Engineered Gold Structures  [招待講演]
    Hiroaki Misawa
    5th Asian Photochemistry Conference (5th APC) 2008年11月 口頭発表(招待・特別) Jiuhua Convention center, Beijing, China
  • 量子ビームによる微細構造形成と新機能発現  [招待講演]
    三澤 弘明
    第57回高分子討論会 2008年09月 口頭発表(招待・特別) 大阪市立大学、大阪
  • Photochemistry on Nano-Engineered Gold Particles  [通常講演]
    Hiroaki Misawa
    XII IUPAC Symposium on Photochemistry 2008 2008年07月 口頭発表(一般) Gothenburg, Sweeden
  • Nano-structured Materials in Photonics and Plasmonics  [招待講演]
    Hiroaki Misawa
    4th SFB 513 Workshop 2008年05月 口頭発表(招待・特別) University of Konstanz, Germany
  • フェムト秒レーザープロセスによるフォトニック結晶の作製  [招待講演]
    三澤 弘明
    電子情報通信学会集積光デバイス技術時限研究専門委員会第3回研究会 2008年05月 口頭発表(招待・特別) 登別温泉ホテルまほろば、登別
  • フェムト秒レーザー加工と高分子デバイス応用への展開  [通常講演]
    三澤 弘明
    日本化学会第88春季年会 2008年03月 口頭発表(一般) 立教大学、東京
  • 光ー分子強結合反応場の創成と展開  [通常講演]
    三澤 弘明
    集積分子工学部門講演会「金属ナノ構造のプラズモニクスト分子回路工学」 2008年03月 口頭発表(一般) 東京工業大学、横浜
  • 北海道大学におけるナノテクノロジー支援事業  [通常講演]
    三澤 弘明
    産学官連携講演会〜科学者・技術者の「ノウハウ」と「先端設備と技術」を連携させた研究、技術・製品開発の支援事業 2008年03月 口頭発表(招待・特別) 千歳科学技術大学、千歳
  • フェムト秒レーザーによる機能性材料の開拓  [招待講演]
    三澤 弘明
    第69回レーザ加工学会講演会 2007年12月 口頭発表(招待・特別) 東京大学、東京
  • Photochemistry on Gold Nanoparticles  [通常講演]
    Hiroaki Misawa
    2007 Korea-Japan Symposium on Frontier Photoscience 2007年11月 口頭発表(一般) Gyeongiu, Korea
  • 多光子重合反応によるマイクロ・ナノ構造の作製  [通常講演]
    三澤 弘明, 上野 貢生, ヨードカジス・サウリウス, ミゼイキス・ビガンタス
    第56回高分子討論会 2007年09月 口頭発表(一般) 名古屋工業大学、名古屋
  • 1000兆分の1秒パルスレーザーが広げる新しい加工技術の可能性−ナノ空間に於ける「光」で北海道に新産業を−」  [通常講演]
    三澤 弘明
    北海道中小企業家同友会産学官連携研究会HoPE9月例会 2007年09月 公開講演,セミナー,チュートリアル,講習,講義等 JSTイノベーションプラザ北海道、札幌
  • ライフサイエンスビジネスの展開について  [通常講演]
    三澤 弘明
    ベンチャー起業のラストワンマイルをつなぎマーケティングセミナー 2007年08月 公開講演,セミナー,チュートリアル,講習,講義等 小樽商科大学札幌サテライト、札幌
  • Nano-Structured Materials in Plasmonics and Photonics  [招待講演]
    Hiroaki Misawa
    The Fifteenth International Conference on COMPOSITES/NANO ENGINEERING (ICCE-15) 2007年07月 口頭発表(基調) Haikou, Hainan Island, China
  • 金属によるナノ空間を使って実現する新しい反応と計測  [招待講演]
    三澤 弘明
    ポストシリコン物質・デバイス創製基盤技術アライアンス発足記念シンポジウム 2007年06月 シンポジウム・ワークショップパネル(指名) 東京
  • 金属ナノ構造による光制御  [招待講演]
    三澤 弘明
    北海道光科学技術研究会講演会 光科学とナノテクノロジー 2007年05月 公開講演,セミナー,チュートリアル,講習,講義等 (独)科学技術振興機構 研究成果活用プラザ北海道、札幌
  • Workshop on Photons and Spins  [通常講演]
    Hiroaki Misawa
    ~Their Generation, Manipulation, and Detection~(Supported by JST-CREST, JSAP, and RIES-Hokudai) 2006年12月 公開講演,セミナー,チュートリアル,講習,講義等 Hokkaido University, Sapporo
  • 表面プラズモンによる微量生体分子計測法の開発  [通常講演]
    三澤 弘明
    LASER EXPO 2006 2006年04月 口頭発表(一般) パシフィコ横浜
  • 材料科学からのフォトニック結晶作製へのアプローチ  [招待講演]
    三澤 弘明
    高分子学会、印刷・情報記録・表示研究会 2005年12月 公開講演,セミナー,チュートリアル,講習,講義等 千里ライフサイエンスセンター、大阪
  • 加工技術としてのフェムト秒レーザ、応用としてのフォトニクス  [招待講演]
    三澤 弘明
    高分子学会、光反応・電子用材料研究会 2005年11月 公開講演,セミナー,チュートリアル,講習,講義等 松下電気厚生年金基金・松心会館、大阪
  • Three-Dimensional Photonic Crystal Structures Recorded by Femtosecond Pulses  [招待講演]
    Hiroaki Misawa
    First Conference on Advanced in Optical Materials 2005年10月 口頭発表(招待・特別) Tucson, Arizona, U.S.A.
  • レーザーとナノテクノロジー  [招待講演]
    三澤 弘明
    (社)レーザー学会 レーザー普及セミナー「未来社会に貢献するレーザー技術」 2005年07月 公開講演,セミナー,チュートリアル,講習,講義等 千里ライフサイエンスセンター、大阪
  • Fabrication of 3D Photonics Structures by Fs-Pulses  [招待講演]
    三澤 弘明
    International Conference on Coherent and Nonlinear Optics and International Conference on Lasers, Applicaions, and Technologies, (ICONO/LAT2005) 2005年05月 口頭発表(招待・特別) St.Petersburg, Russia
  • Holographic and direct laser writing of photonic crystal structures  [招待講演]
    Hiroaki Misawa
    ISG/ICG 2005 2005年04月 口頭発表(招待・特別) Shanghai, China
  • Femtosecond Laser Fabrication of 3D Photonic Crystal Structures  [招待講演]
    Hiroaki Misawa
    The 6th International Symposium on Laser Precision Microfabrication 2005年04月 口頭発表(招待・特別) Williamsburg, U.S.A
  • 3D Photonic Crystal Structures Recorded by Femtosecond Laser Irradiation  [招待講演]
    Hiroaki Misawa, Saulius Juodkazis
    The 2nd International Symposium on Mechanical Science based on Nanotechnology 2005年02月 口頭発表(招待・特別) 仙台国際センター、仙台市
  • フェムト秒レーザーによる新しい3次元加工法の加工法の開発とその応用  [招待講演]
    三澤 弘明
    2005年01月 室蘭工業大学、室蘭
  • 量子相関光子ビームによるナノ加工技術の確立を目指して  [通常講演]
    三澤 弘明
    北海道電子科学研究所 研究交流会 2005年01月 公開講演,セミナー,チュートリアル,講習,講義等 北海道大学学術交流会館、札幌
  • Femtosecond Laser Fabrication of Photonic Crystal Structures  [通常講演]
    H. Misawa, V. Mizeikis, S. Juodkazis, S. Matsuo, T. Kondo, S. K. Khen
    7th Annual Symposium on JAFoS 2004年12月 ポスター発表 LA. USA
  • Femtosecond Laser Fabrication of Photonic Crystal Structures  [通常講演]
    Hiroaki Misawa
    International Workshop on Photonic-crystal Devices and Their Applications 2004年10月 口頭発表(一般) National Taiwan Normal University, Taipei, Taiwan
  • フェムト秒レーザーパルスによる3次元加工  [通常講演]
    三澤 弘明
    日本学術振興会 未踏・ナノデバイステクノロジー第151委員会 2004年07月 公開講演,セミナー,チュートリアル,講習,講義等 ふらのラテール、北海道富良野市
  • フェムト秒加工のナノバイオ分野への応用  [通常講演]
    三澤 弘明
    産総研ナノバイオ分野人材養成ユニット講義 2004年03月 公開講演,セミナー,チュートリアル,講習,講義等 産総研関西センター、大阪
  • 高分子材料を用いたナノ・マイクロ周期構造作製技術の開発  [通常講演]
    三澤 弘明
    2003年度印刷・情報記録・表示研究会講座 2004年02月 公開講演,セミナー,チュートリアル,講習,講義等 発明会館ホール、東京 高分子学会
  • 北大発ベンチャー企業「(株)レーザーシステム」の立ち上げと最近の研究成果の紹介  [招待講演]
    三澤 弘明
    (財)光産業技術振興協会 平成16年度第2回フェムト秒超加工研究会 2004年 公開講演,セミナー,チュートリアル,講習,講義等 光産業技術振興協会、東京)
  • フェムト秒レーザーを用いた3次元加工技術  [通常講演]
    三澤 弘明
    Sony Institute of Technology 2003年11月 公開講演,セミナー,チュートリアル,講習,講義等
  • フェムト秒レーザー加工のナノテクノロジーへの展開  [通常講演]
    三澤 弘明
    日本機械学会・特別講演会 2003年11月 公開講演,セミナー,チュートリアル,講習,講義等 徳島大学、徳島
  • フェムト秒レーザーによる3次元超加工技術の現状  [通常講演]
    三澤 弘明
    第2回フェムト秒レーザー加工技術研究会 2003年10月 公開講演,セミナー,チュートリアル,講習,講義等 北九州テクノセンター、北九州
  • 高分子材料を用いたフォトニック結晶作製技術の開発  [通常講演]
    三澤 弘明
    フォトポリマー懇話会 第145回フォトポリマー懇話会例会「Two-photon Sensitization」 2003年10月 公開講演,セミナー,チュートリアル,講習,講義等 東京理科大学・理窓会館、東京
  • フェムト秒レーザー加工とそのフォトニック結晶作製への展開  [通常講演]
    三澤 弘明
    日本学術振興会・光エレクトロニクス第130委員会第235回研究会 2003年10月 公開講演,セミナー,チュートリアル,講習,講義等 森戸記念館、東京
  • Holographic and Direct Recording by Femtosecond Pulses  [通常講演]
    H. Misawa, T. Kondo, K. Yamasaki, S. Juodkazis, V. Mizeikis, S. Matsuo
    IUMRS-ICAM2003 2003年10月 口頭発表(一般) Pacifico Yokohama, Yokohama
  • 高分子材料を用いた3次元フォトニック結晶の作製  [通常講演]
    三澤 弘明
    電子情報通信学会ソサイアティOPE/LQE合同シンポジウム 「SC-1フォトニック結晶の最近の動向:基礎から応用まで」 2003年09月 シンポジウム・ワークショップパネル(指名) 新潟大学
  • フェムト秒レーザーとそのマイクロ・ナノテクノロジーへの展開  [通常講演]
    三澤 弘明
    長岡技術科学大学匠稜講演会 2003年09月 公開講演,セミナー,チュートリアル,講習,講義等 長岡技術科学大学
  • フェムト秒レーザー加工の新展開  [通常講演]
    三澤 弘明
    先端レーザー加工技術研究会 2003年09月 公開講演,セミナー,チュートリアル,講習,講義等 信濃川テクノポリス機構、新潟
  • マイクロ・ナノ加工による新しい機能性材料の創出  [通常講演]
    三澤 弘明
    日本機械学会 2003年09月 公開講演,セミナー,チュートリアル,講習,講義等 愛媛大学工学部
  • フェムト秒多光束干渉による3 次元ナノ構造の作製  [通常講演]
    三澤 弘明
    2003年秋季第64回応用物理学関係連合講演会 フェムト秒レーザーを用いたマテリアルプロセシングの新展開 2003年08月 口頭発表(一般) 福岡大学、福岡
  • 新規DNAハイブリダイゼーション検出技術の開発  [通常講演]
    三澤 弘明
    日本機械学会2003年度年次大会先端技術フォーラム レーザー精密微細加工の現状と将来技術 2003年08月 口頭発表(一般) 徳島大学工学部、徳島
  • 光が拓くナノテクノロジー  [招待講演]
    三澤 弘明
    北海道大学院共通授業「ナノテクノロジー・ナノサイエンスの展開 I」 2003年08月 公開講演,セミナー,チュートリアル,講習,講義等 北海道大学、札幌
  • フェムト秒レーザーパルスを用いた3次元加工技術の開発  [招待講演]
    三澤 弘明
    キャノン講演会 2003年07月 公開講演,セミナー,チュートリアル,講習,講義等
  • Three-dimensional Recording by Femtosecond Pulses in Polymer Materials  [通常講演]
    三澤 弘明
    第20回フォトポリマーコンファレンス 国際シンポジウム2003 マイクロリソグラフィとナノテクノロジー材料とプロセスの最前線 2003年06月 シンポジウム・ワークショップパネル(指名) 千葉大学、千葉
  • Towards novel techniques of optical nanoprocessing  [通常講演]
    Hiroaki Misawa
    CREST & Quantum, Nanoplanar, Nanostructures & Nanoelectronics 2003 Joint International Workshop 2003年06月 口頭発表(一般) Awaji Yumebutai International Conference Center
  • Three-dimensional microfabrication by femtosecond pulses in dielectrics  [通常講演]
    H. Misawa, T. Kondo, S. Matsuo, S. Juodkazis, V. Mizeikis
    E-MRS 2003 Spring Meeting 2003年06月 口頭発表(一般) Strasbourg France
  • 2光子励起による透明材料の加工  [通常講演]
    三澤 弘明
    03-1光反応・電子用材料研究会 2003年05月 公開講演,セミナー,チュートリアル,講習,講義等 東京工業大学、東京
  • フェムト秒レーザー加工  [通常講演]
    三澤 弘明
    (社)表面技術協会第105回講演会 2003年03月 公開講演,セミナー,チュートリアル,講習,講義等 茨城
  • フェムト秒レーザーによる3次元マイクロ加工  [通常講演]
    三澤 弘明
    Mate 2003 第9回「エレクトロニクスにおけるマイクロ接合・実装技術」 2003年02月 口頭発表(一般) パシフィコ横浜
  • Three-dimensional recording by femtosecond pulses in dielectrics  [通常講演]
    H. Misawa, T. Kondo, S. Matsuo, S. Juodkazis, V. Mizeikis
    Photonics West「Laser Applications Microelectronics and Optoelectronic Manufacturing VIII」 2003年01月 口頭発表(一般) San Jose, USA
  • 多光子励起による透明材料の三次元加工  [通常講演]
    三澤 弘明
    東北大学多元物質科学研究所国際シンポジウム ナノフォトニックポリマーの展開 2003年01月 シンポジウム・ワークショップパネル(指名) 東北大学、仙台
  • フェムト秒レーザーによるサファイア等各種光学結晶の内部改質とそのメカニズム  [通常講演]
    三澤 弘明
    第4回 フェムト秒超加工研究会 2003年01月 公開講演,セミナー,チュートリアル,講習,講義等 日本科学未来館、東京
  • フェムト秒レーザー加工による材料の高付加価値化とその将来展望  [通常講演]
    三澤 弘明
    分野設定型研究会「微細加工装置(レーザー加工技術)分野」第2回セミナー 2003年01月 公開講演,セミナー,チュートリアル,講習,講義等
  • 光圧による物質の化学構造・運動制御  [通常講演]
    三澤 弘明
    第6回 NAIST科学技術セミナー「偏光と物質の相互作用」 2003年01月 公開講演,セミナー,チュートリアル,講習,講義等 奈良先端科学技術大学院大学、奈良
  • Fabrication and Characterization of Photonic Structures  [通常講演]
    H. Misawa
    ICNME 2002 2002年12月 公開講演,セミナー,チュートリアル,講習,講義等 Miko, Kobe
  • 透明材料の多光子励起加工と量子相関光子加工  [通常講演]
    三澤 弘明
    ミニシンポジウム「分子・クラスター・アセンブリーによる光シンクロ現象とデバイス」 2002年11月 シンポジウム・ワークショップパネル(指名) 福岡
  • レーザーを用いたマイクロ・ナノテクノロジー開発への挑戦  [通常講演]
    三澤 弘明
    2002年11月 公開講演,セミナー,チュートリアル,講習,講義等 宇部興産
  • 表面プラズモン共鳴を用いた次世代マイクロDNAチップの開発  [通常講演]
    三澤 弘明
    2002年10月 公開講演,セミナー,チュートリアル,講習,講義等 関西学院大学、兵庫
  • フェムト秒レーザー加工法とその応用  [通常講演]
    三澤 弘明
    徳島産学創造パートナーズ設立総会 2002年09月 公開講演,セミナー,チュートリアル,講習,講義等 地域共同研究センター、徳島
  • Processing of sapphire and glass materials after femtosecond exposure  [通常講演]
    A. Marcinkevicius, R. Waki, S. Juodkazis, S. Matsuo, H. Misawa
    2002年09月 Orland
  • 量子相関光とナノサイエンス  [通常講演]
    三澤 弘明
    応用物理学会 有機分子・バイオエレクトロニクス分科会(M&BE)および有機エレクトロニクス材料研究会(JOEM)共催研究会「新しい光源が変えるナノサイエンス、バイオテクノロジーの世界」 2002年09月 公開講演,セミナー,チュートリアル,講習,講義等 東京大学・山上会館、東京
  • レーザープロセシングとナノテクノロジー  [通常講演]
    三澤 弘明
    (社)日本分光学会第38回夏期セミナー「レーザープロセシングと分光学」 2002年09月 公開講演,セミナー,チュートリアル,講習,講義等 幕張メッセ、千葉
  • フォトニック結晶の作成技術とその応用  [通常講演]
    三澤 弘明
    バッファーレイヤー調査研究員会 2002年08月 公開講演,セミナー,チュートリアル,講習,講義等 つくば
  • 光によるナノ加工への挑戦  [通常講演]
    三澤 弘明
    徳島大学地域共同研究センターナノ医療技術応用研究会 −ナノ技術に未来を見つめて− 2002年07月 公開講演,セミナー,チュートリアル,講習,講義等 徳島大学工業会館、徳島
  • Advantages and Shortcomings of Femtosecond Laser Microfabrication  [通常講演]
    H. Misawa, S. Juodkazis, S. Matsuo, V. Mizeikis, A. Marcinkevicius
    2002 Japan-USA Symposium on Flexible Automation 2002年07月 シンポジウム・ワークショップパネル(指名) International Conference Center Hiroshima, Hiroshima
  • フェムト秒レーザーとナノテクノロジー  [通常講演]
    三澤 弘明
    レーザー学会主催「レーザーエキスポ2002」特別セミナー 2002年04月 公開講演,セミナー,チュートリアル,講習,講義等 幕張
  • 医療技術を目指したマイクロチップ  [通常講演]
    三澤 弘明
    産総研四国センター研究講演会 2002年02月 公開講演,セミナー,チュートリアル,講習,講義等 高松
  • 超短パルスレーザーによる透明材料の微細加工  [通常講演]
    三澤 弘明
    レーザー学会学術講演会第22回年次大会 2002年01月 口頭発表(一般) 大阪
  • 極短パルスレーザーによる革新的加工技術の現状とナノ加工への期待  [通常講演]
    三澤 弘明
    第125回科学技術セミナー 2001年12月 公開講演,セミナー,チュートリアル,講習,講義等 滋賀
  • フェムト秒レーザーによる化学反応の空間制御  [通常講演]
    三澤 弘明
    化学工学講習会 2001年12月 公開講演,セミナー,チュートリアル,講習,講義等 岡山
  • 集光フェムト秒レーザーによるフォトニック結晶構造の作製  [通常講演]
    三澤 弘明
    最近の分光学の進歩に関する講演会 2001年11月 公開講演,セミナー,チュートリアル,講習,講義等 大阪
  • Micro-fabrication of three-dimensional photonic crystal structures photopolymerization of resins  [通常講演]
    H. Misawa, S.Matsuo, T. Kondo, V. Mizeikis, H.-B. Sun
    Multi-dimentional Microscopy 2001 2001年11月 公開講演,セミナー,チュートリアル,講習,講義等 Melbourne, Australia
  • 透明誘電体材料のフェムト秒超加工  [通常講演]
    三澤 弘明
    (株)リコー研究開発本部特別講演会 2001年10月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • ナノテクでのフェムト秒レーザー加工の理論と実践  [通常講演]
    三澤 弘明
    電気硝子工業会第16回技術セミナー 2001年10月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • Application of Femtosecond Laser pulses for Microfabrication of Transparent Media  [通常講演]
    H. Misawa, V. Mizeikis, S. Juodkazis, A. Marcinkevicius, H.-B. Sun, S.Matsuo
    COLA’01 2001年10月 口頭発表(一般) EPOCHAL TSUKUBA Tsukuba
  • フェムト秒レーザプロセッシングの魅力  [通常講演]
    三澤 弘明
    2001年度精密工学会秋季大会シンポジウム 2001年09月 シンポジウム・ワークショップパネル(指名) 大阪
  • フェムト秒超加工技術とそのフォトニック結晶作製への応用  [通常講演]
    三澤 弘明
    技術情報協会セミナー 2001年09月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • 透明材料のフェムト秒超加工  [通常講演]
    三澤 弘明
    平成13年度電気学会電子・情報システム部門大会 2001年09月 口頭発表(一般) 沖縄
  • 微小技術の開発動向展望 ─ナノテクノロジーへの展開─  [通常講演]
    三澤 弘明
    京都工業会セミナー 2001年08月 公開講演,セミナー,チュートリアル,講習,講義等 京都
  • 集光フェムト秒レーザーによる機能性微小構造の作製  [通常講演]
    三澤 弘明
    光産業技術振興協会 平成13年度第1回フェムト秒超加工研究会 2001年07月 シンポジウム・ワークショップパネル(指名) 東京
  • 集光レーザービームによる透明材料の超加工  [通常講演]
    三澤 弘明
    ナノテクノロジーとしての光化学の新展開に関する研究会 2001年07月 公開講演,セミナー,チュートリアル,講習,講義等 大阪
  • 超高密度フォトンが拓く3次元マイクロ・ナノエンジニアリング  [通常講演]
    三澤 弘明
    平成13年度フォトンテクノロジー技術部会主催公開セミナー 2001年07月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • フェムト秒レーザーによる透明材料の超加工  [通常講演]
    三澤 弘明
    フェムト秒ナノ加工技術の展開シンポジウム 2001年07月 シンポジウム・ワークショップパネル(指名) 大阪
  • Stereolithography and 3D micro-structuring of transparent materials by femtosecond laser irradiation  [通常講演]
    H. Misawa, S. Juodkazis, V. Mizeikis, A. Marcinkevicius, S. Matsuo
    VII International Conference ILLA-2001, Laser and laser-information Technologies 2001年06月 口頭発表(一般) Vladimir-Shatura, Russia
  • 集光フェムト秒レーザーによる加工の世界的動向 : フォトニック結晶から 医療応用まで  [通常講演]
    三澤 弘明
    集光フェムト秒レーザーが創る21世紀のナノフォトニクスシンポジウム 2001年05月 シンポジウム・ワークショップパネル(指名) 東京
  • Microfabrication by Using Femtosecond Irradiation  [通常講演]
    H. Misawa, A. Marcinkevicius, S. Juodkazis, M. Watabnabe, V. Mizeikis, S. Matsuo
    MRS, Spring 2001 Meeting 2001年04月 口頭発表(一般) San Francisco, California, USA
  • 集光フェムト秒レーザーによる3次元周期構造の作製  [通常講演]
    三澤 弘明
    第47回東京工業大学総合研究館講演会 2001年03月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • 集光レーザービームによるフォトニックナノ構造の創製  [通常講演]
    三澤 弘明
    平成12年度日本表面科学会東北支部講演会 2001年03月 公開講演,セミナー,チュートリアル,講習,講義等 石巻、仙台
  • 集光フェムト秒レーザーを用いた3次元微細加工  [通常講演]
    三澤 弘明
    公開シンポジウム、ナノ光学応用に向けたレーザーと有機物質の相互作用 2001年02月 公開講演,セミナー,チュートリアル,講習,講義等 大阪
  • 透明物質の多光子3次元レーザー加工  [通常講演]
    三澤 弘明
    レーザー学会学術講演会第21回年次大会 2001年01月 口頭発表(一般) 東京
  • Time-resolved study of femtosecond microfabrication in sillica glass  [通常講演]
    H. Misawa, S. Juodkazis, A. Marcinkevicius, M. Watanabe, V. Mizeikis, S. Matsuo
    Laser Applications in Microelectronic and Optoelectronic Manufacturing VI (LA09), Part of SPIE'S International Symposium on High-Power Lasers and Applications 2001年01月 口頭発表(一般) San Jose, USA
  • 光学的な微細構造の形成  [通常講演]
    三澤 弘明
    日本光学会第27回冬期講習会 2001年01月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • 放射圧による分子マニピュレーション  [通常講演]
    三澤 弘明
    第7回分子システムセミナー 2001年01月 公開講演,セミナー,チュートリアル,講習,講義等 九州
  • 高分子微粒子や光硬化樹脂を用いた3次元有機フォトニック結晶  [招待講演]
    三澤 弘明
    第116回有機エレクトロニクス材料研究会 2000年12月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • フェムト秒レーザー加工による周期構造の作製とそのフォトニック結晶への応用  [通常講演]
    三澤 弘明
    フォトニック結晶研究会 2000年12月 公開講演,セミナー,チュートリアル,講習,講義等 つくば
  • 医療応用を目指したマイクロチップの開発  [通常講演]
    三澤 弘明
    第14回日本エム・イー学会秋季大会 2000年10月 口頭発表(一般) 徳島
  • Laser Micro-Fabrication / Manipulation of Dielectric Materials  [通常講演]
    三澤 弘明
    2000 International Symposium on Micromechatronics and Human Science 2000年10月 口頭発表(一般) 名古屋
  • フェムト秒レーザープロセシングが拓く微小空間の世界  [通常講演]
    三澤 弘明
    第2回先進レーザ応用技術セミナー 2000年10月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • フェムト秒レーザー加工と3次元光学  [通常講演]
    三澤 弘明
    第61回応用物理学会学術講演会 2000年09月 口頭発表(一般) 北海道
  • 断熱的3次元レーザー加工-フォトニック結晶の作製に向けて  [通常講演]
    三澤 弘明
    第61回応用物理学会学術講演会 2000年09月 口頭発表(一般) 北海道
  • フォトニック結晶の作製と評価  [通常講演]
    三澤 弘明
    第1回ナノ・フォトニッククリスタルの作製と評価 2000年07月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • 有機系フォトニッククリスタルの特徴と可能性  [通常講演]
    三澤 弘明
    第38回有機デバイス研究会 2000年07月 公開講演,セミナー,チュートリアル,講習,講義等 静岡
  • Formation of Photonic Crystals by Femtosecond Laser Microfabrication  [通常講演]
    H. Misawa, S. Juodkazis, H.-B. Sun, S. Matuso, J. Nishii
    First International Symposium on Laser Precision Microfabrication 2000年06月 口頭発表(一般) Omiya, Saitama
  • フェムト秒レーザーを用いた3次元光加工  [通常講演]
    三澤 弘明
    工業技術会セミナー −次世代半導体レーザー記録材料と感光材料の新展開− 2000年06月 公開講演,セミナー,チュートリアル,講習,講義等 東京
  • Two-dimensional Silicon-Based Photonic Crystals  [通常講演]
    三澤 弘明
    第3回大阪大学産業科学研究所国際シンポジウム 2000年03月 シンポジウム・ワークショップパネル(指名) 大阪
  • Multi-photon Recording Two-Photon Reading of a Three-dimensional Rewritable Optical Memory  [通常講演]
    三澤 弘明
    第3回大阪大学産業科学研究所国際シンポジウム 2000年03月 シンポジウム・ワークショップパネル(指名) 大阪
  • Laser Microfabrication -a New Tool for Tailoring Three-dimensional Photonic Band Gap Crystals  [通常講演]
    三澤 弘明
    PECS 2000年03月 仙台
  • Two Topics on Photonic Crystals: Si-Based 2D Lattices and fs-Laser-Induced 3D Structures  [通常講演]
    三澤 弘明
    フォトニック結晶筑波ワークショップ 2000年02月 シンポジウム・ワークショップパネル(指名) 筑波
  • 医療応用を目指したマイクロ集積化分析システムの開発  [通常講演]
    三澤 弘明
    特許流通フェアin四国2000〜未来を見つめるエジソンに出会えます〜 2000年02月 公開講演,セミナー,チュートリアル,講習,講義等 徳島
  • Microfabrication by Femtosecond Laser Irradiation  [通常講演]
    H. Misawa, H.-B. Sun, S. Juodkazis, M. Watanabe, S. Matsuo
    SPIE International Symposium LASE 2000/LAMOM-V 2000年01月 口頭発表(一般) San Jose
  • 臨床分析チップ  [通常講演]
    三澤 弘明
    高分子学会 2000年01月 口頭発表(一般) 徳島大学工業会館メモリアルホール
  • マイクロトータルアナリシスシステムによる極微粒分析の試み  [通常講演]
    三澤 弘明
    分析技術研究会のご案内−最新の医薬分析とマイクロ分析技術ー 1999年12月 口頭発表(一般) 徳島
  • マイクロ集積化分析システムの開発  [通常講演]
    三澤 弘明
    平成11年度創造的中小企業研究開発支援事業、研究開発交流会 1999年12月 公開講演,セミナー,チュートリアル,講習,講義等 愛媛大学
  • マイクロマシン技術の化学への展開  [招待講演]
    三澤 弘明
    群嶺テクノセミナー 1999年10月 公開講演,セミナー,チュートリアル,講習,講義等 群馬高専
  • レーザー多光子吸収による三次元マイクロファブリケーション  [通常講演]
    三澤 弘明
    立命館大学SRセンターセミナー 1999年10月 公開講演,セミナー,チュートリアル,講習,講義等 滋賀
  • 多光子三次元マイクロファブリケーション  [通常講演]
    三澤 弘明
    第60回応用物理学会学術講演会 1999年09月 口頭発表(一般) 神戸
  • サブマイクロメートル領域における分光計測  [通常講演]
    三澤 弘明
    スプラ金属錯体における物性研究の現状と展望(スプラ金属錯研究会) 1999年08月 公開講演,セミナー,チュートリアル,講習,講義等 名古屋
  • 多光子吸収を利用した三次元マイクロファブリケーション  [通常講演]
    三澤 弘明
    1999年07月 公開講演,セミナー,チュートリアル,講習,講義等 財団法人製造科学技術センターフォトンセンター、高松
  • マイクロ化学 -材料加工から集積化分析システムへ-  [通常講演]
    三澤 弘明
    マイクロ談話会 1999年06月 公開講演,セミナー,チュートリアル,講習,講義等 京都
  • 多光子吸収を利用した精密三次元造形  [通常講演]
    三澤 弘明
    高分子講演会 1999年06月 公開講演,セミナー,チュートリアル,講習,講義等 京都
  • マイクロ造形法を用いたフォトニック結晶作製技術の開発  [通常講演]
    三澤 弘明
    SEMIジャパンマイクロマシンセミナー 1999年06月 公開講演,セミナー,チュートリアル,講習,講義等 大阪
  • Three-Dimensional Optical Data Storage in Vitreous Silica  [通常講演]
    H. Misawa, S. Juodkazis
    NAIR/OITDA Workshop on Ultrahigh Density Data Storage 1999年03月 シンポジウム・ワークショップパネル(公募) Tsukuba
  • マイクロマシン技術の光化学への展開  [通常講演]
    三澤 弘明
    平成10年度第2会光化学協会講演会 1998年12月 公開講演,セミナー,チュートリアル,講習,講義等
  • 多光子励起による石英ガラスへの三次元光記録  [通常講演]
    三澤 弘明, 松尾繁樹, 渡邊満
    レーザー顕微鏡研究会第21回講演会 1998年 口頭発表(一般)
  • フェトム秒レーザーによる三次元配列構造の作製とその光学的特性  [通常講演]
    三澤 弘明
    第59回応用物理学会学術講演会シンポジウム 1998年 口頭発表(一般)
  • 多光子励起による石英ガラス中への光記録  [通常講演]
    三澤 弘明
    第59会応用物理学会学術講演会シンポジウム 1998年 口頭発表(一般)
  • レーザーによる超微粒子の捕捉・制御  [通常講演]
    三澤 弘明
    '98国際粉体工業展 1998年 口頭発表(一般)
  • 超高密度フォトン場を利用した新しい光科学  [通常講演]
    三澤 弘明
    第115回ニュー・フロンティア材料研究会 1997年 公開講演,セミナー,チュートリアル,講習,講義等
  • レーザー顕微鏡を用いた微小構造物の作製  [通常講演]
    三澤 弘明
    第13回ラピッド・プロトタイピングシンポジウム 1997年 シンポジウム・ワークショップパネル(指名)
  • 超高密度フォトン場を利用した光科学  [通常講演]
    三澤 弘明
    第17回物理化学コロキュウム「マテリアルケミストリー」 1997年 公開講演,セミナー,チュートリアル,講習,講義等 日本化学会東北支部
  • 光圧ハンドリング  [通常講演]
    三澤 弘明
    第2回メカフォトフォーラム、(NTT境界領域研究所) 1993年 公開講演,セミナー,チュートリアル,講習,講義等
  • レーザーマニピュレーション−高分子微粒子の三次元操作  [通常講演]
    三澤 弘明
    93/1高分子可能性講座、高分子の構造・物性・モルホロジー制御の最前線 1993年
  • 光マニピュレ−ション法の化学への応用  [通常講演]
    三澤 弘明
    エキシマレーザーを用いた高分子膜の表面改質 1993年
  • Laser-scanning Manipulation in Microchemistry  [招待講演]
    H. Misawa
    OPTCON '92 1992年11月 口頭発表(招待・特別) Boston
  • マイクロメーター微粒子のレザーマニピュレ−ションと反応  [通常講演]
    三澤 弘明
    日本化学会第63春季年会 1992年03月 口頭発表(一般) 近畿大学、大阪
  • レーザートラッピングとマイクロマシン −化学の立場から−  [通常講演]
    三澤 弘明
    マイクロマシンからナノマシンへ調査研究分科会(日本機械学会) 1992年 公開講演,セミナー,チュートリアル,講習,講義等
  • レーザーでマイクロメートル微粒子を操作し化学する  [通常講演]
    三澤 弘明
    第7会技術放談会−生命現象を計測する−(筑波研究コンソーシアム) 1992年 公開講演,セミナー,チュートリアル,講習,講義等
  • レーザーによるマイクロメートル微粒子のプロセシング  [通常講演]
    三澤 弘明
    化学工学会第25回秋季大会 1992年 口頭発表(一般)
  • フォトンで操る材料構築  [通常講演]
    三澤 弘明
    第16回革新領域セミナー、光電子材料のインテリジェント化のアプローチ 1992年 公開講演,セミナー,チュートリアル,講習,講義等
  • レーザーマニピュレーション −化学への展開−  [通常講演]
    三澤 弘明
    筑波研究フォーラム(筑波研究コンソーシアム) 1991年 公開講演,セミナー,チュートリアル,講習,講義等
  • レーザーマニピュレーションと極微化学  [通常講演]
    三澤 弘明
    第6回若い世代の特別講演会(日本化学会) 1991年 公開講演,セミナー,チュートリアル,講習,講義等

作品等

  • 微粒子反応とその計測方法(特許・国外)
    1993年
  • 粒子動態の制御方法(特許・国外)
    1993年
  • Method for Forming Particulate Reaction and Measuring Method Thereof
    1993年
  • Method for Forming and Denaturing Particles
    1993年
  • 極微小光源の形成方法(特許・国外)
    1992年
  • マルチビーム微粒子操作法(特許・国外)
    1992年
  • 微粒子の吸収スペクトルの計測方法 (特許)
    1992年
  • レーザー光を用いたマイクロマシンの駆動装置 (特許)
    1992年
  • Method for Forming Microilluminants
    1992年
  • Method for multi-Beam Manipulation of Micromanipulation
    1992年
  • Method for Measurment of Absorption Spectrum of a Single Microparticle
    1992年
  • Method for Actuation of Micromachine by Laser Beam
    1992年
  • レーザートラッピング方法(特許・国外)
    1991年
  • 微細修飾・加工方法(特許・国外)
    1991年
  • Laser Trapping and Method for Applications Thereof(Scanning)
    1991年
  • Laser Microprocessing and the Device Thereof
    1991年
  • 微粒子動態パターン(レーザー走査型微粒子パターン形成および輸送装置) (特許)
    1990年
  • 微粒子動態パターン(顕微マイクロ微粒子修飾・加工装置を用いた新しいマイクロメートル空間パターンの形成)(特許)
    1990年
  • マイクロカプセルプロセシング(顕微マイクロ微粒子修飾・加工装置のマイクロカプセルへの応用と展開)(特許)
    1990年
  • Method for Formation of Dinamic Pattern of Microparticles
    1990年
  • Method for Formation of Dinamic Pattern of Microparticles
    1990年
  • Microprocessing of Microcapsules
    1990年
  • 顕微マイクロ分光装置とその方法 (特許)
    1989年
  • 顕微マイクロ微粒子修飾・加工装置とその方法 (特許)
    1989年
  • Instrument of Microspectroscopy and Method for Application Thereof
    1989年
  • Microprocessing of Microparticles and the Device Thereof
    1989年

その他活動・業績

  • 上野貢生, YANG Jinghuan, YANG Jinghuan, 巽亮太, SUN Quan, 押切友也, 三澤弘明, 三澤弘明 応用物理学会春季学術講演会講演予稿集(CD-ROM) 66th ROMBUNNO.10p‐W621‐3 2019年02月25日 [査読無し][通常論文]
  • 大西梓, ZU Shuai, SHI Xu, SUN Quan, 押切友也, 上野貢生, 三澤弘明, 三澤弘明 応用物理学会春季学術講演会講演予稿集(CD-ROM) 66th ROMBUNNO.9a‐W621‐9 2019年02月25日 [査読無し][通常論文]
  • SUN Quan, YANG Jinghuan, YANG Jinghuan, UENO Kosei, SHI Xu, OSHIKIRI Tomoya, MISAWA Hiroaki, MISAWA Hiroaki 応用物理学会春季学術講演会講演予稿集(CD-ROM) 66th ROMBUNNO.9p‐W331‐8 2019年02月25日 [査読無し][通常論文]
  • 菅浪誉騎, 押切友也, SHI Xu, SUN Quan, 上野貢生, 三澤弘明, 三澤弘明 光化学討論会要旨集(CD-ROM) 2019 2019年
  • 佐合芽生, 唐津孝, 上野貢生, 三澤弘明, 黒沼慎, 荒木保幸, 和田健彦 シンポジウム「モレキュラー・キラリティー」講演要旨集 2018 2018年
  • 上田慎二, 長谷川誠樹, 市川陽一, 上野貢生, 三澤弘明, 岡本裕巳, 井村考平 応用物理学会秋季学術講演会講演予稿集(CD-ROM) 79th 2018年
  • 中村圭佑, 押切友也, SHI Xu, 上野貢生, 三澤弘明, 三澤弘明 日本化学会春季年会講演予稿集(CD-ROM) 98th 2018年
  • 高倉稜平, 押切友也, 上野貢生, 近藤敏彰, 益田秀樹, 三澤弘明, 三澤弘明 日本化学会春季年会講演予稿集(CD-ROM) 98th 2018年
  • 押切友也, 上野貢生, 三澤弘明, 三澤弘明 触媒 60 (3) 2018年
  • 上野貢生, SHI Xu, SUN Quan, 押切友也, 笹木敬司, 三澤弘明, 三澤弘明 高分子学会予稿集(CD-ROM) 67 (2) 2018年
  • 城春樹, 押切友也, 上野貢生, 三澤弘明, 三澤弘明 光化学討論会要旨集(CD-ROM) 2018 2018年
  • Kosei Ueno, Quan Sun, Hiroaki Misawa Advanced Photonics 2018 (BGPP, IPR, NP, NOMA, Sensors, Networks, SPPCom, SOF) 2018年 [査読有り][通常論文]
  • 押切 友也, 上野 貢生, 三澤 弘明 機能材料 37 (8) 40 -49 2017年08月 [査読無し][通常論文]
  • 高倉稜平, 押切友也, 上野貢生, 近藤敏彰, 益田秀樹, 三澤弘明, 三澤弘明 日本化学会春季年会講演予稿集(CD-ROM) 97th 2017年
  • 中村圭佑, 押切友也, SHI Xu, 上野貢生, 三澤弘明, 三澤弘明 光化学討論会要旨集(CD-ROM) 2017 2017年
  • 山田拓樹, 押切友也, SUN Quan, 上野貢生, 三澤弘明, 三澤弘明 光化学討論会要旨集(CD-ROM) 2017 2017年
  • 押切 友也, 上野 貢生, 三澤 弘明 色材協会誌 90 (12) 408 -413 2017年 [査読無し][通常論文]
     
    <p>光化学反応を利用した機能性材料や光エネルギー変換系はわれわれの豊かな生活を支えるために必要不可欠なものとなっている。しかし,一般的な分子の吸収断面積は小さく,一つの光子を1,000万にも及ぶ分子と相互作用させることによって初めてその中の1分子が励起される。効率的な光反応を実現するためには,光と物質の相互作用を増大させ,入射した光をきわめて少ない物質量により完全に吸収する高効率な光励起プロセスを可能にする光反応場の設計・構築が必要となる。一方,金属ナノ微粒子が示す局在表面プラズモンは,可視~近赤外領域での入射光を時間的・空間的に閉じ込めることで有効に利用可能な光捕集アンテナとして研究されてきた。筆者らは,これまでに緻密に設計・作製した金属ナノ構造が示す局在表面プラズモンのさまざまな性質について研究を進めてきた。本稿では,局在表面プラズモンが形成する光反応場が可能にする特異な光化学反応,とくに可視光を用いた光-化学エネルギー変換反応の現状について解説する。</p>
  • 大塚 俊明, 松尾 保孝, 坂入 正敏, 鈴木 啓太, 上野 貢生, 孫 泉, 三澤 弘明, スバギョ アグス, 末岡 和久 金属 86 (12) 1103 -1111 2016年12月 [査読無し][通常論文]
  • 押切 友也, 上野 貢生, 三澤 弘明 光化学 = Photochemistry : 光化学協会会誌 47 (1) 2 -8 2016年04月 [査読無し][通常論文]
  • 押切 友也, 上野 貢生, 三澤 弘明 ファインケミカル : 調査・資料・報道・抄録 45 (3) 41 -46 2016年03月 [査読無し][通常論文]
  • 中村圭佑, 片瀬貴義, 押切友也, 上野貢生, 太田裕道, 三澤弘明 日本化学会春季年会講演予稿集(CD-ROM) 96th 2016年
  • 高倉稜平, 押切友也, 上野貢生, WU Hui-Ping, DIAU Eric W., 近藤敏彰, 益田秀樹, 三澤弘明, 三澤弘明 日本化学会春季年会講演予稿集(CD-ROM) 96th 2016年
  • 澤柳博輝, 中村圭佑, 押切友也, 上野貢生, 三澤弘明 日本化学会春季年会講演予稿集(CD-ROM) 96th 2016年
  • 上野貢生, 野澤翔, 三澤弘明 日本化学会講演予稿集 95th (3) 2015年
  • 中村圭佑, 片瀬貴義, 押切友也, 上野貢生, 太田裕道, 三澤弘明 日本化学会講演予稿集 95th (2) 2015年
  • 増永梨合花, 押切友也, 上野貢生, 三澤弘明 日本化学会講演予稿集 95th (2) 2015年
  • 上野貢生, 野澤翔, 三澤弘明 応用物理学会春季学術講演会講演予稿集(CD-ROM) 62nd 2015年
  • 上原日和, 押切友也, 上野貢生, 三澤弘明 日本化学会講演予稿集 95th (2) 2015年
  • 押切友也, 上野貢生, 三澤弘明 日本化学会講演予稿集 95th (2) 2015年
  • 押切友也, 上野貢生, 三澤弘明 光化学討論会要旨集(CD-ROM) 2015 2015年
  • 増永梨合花, 押切友也, 上野貢生, 三澤弘明 光化学討論会要旨集(CD-ROM) 2015 2015年
  • 澤柳博輝, 中村圭佑, 押切友也, 上野貢生, 三澤弘明 光化学討論会要旨集(CD-ROM) 2015 2015年
  • 上野貢生, 野澤翔, 三澤弘明 光化学討論会要旨集(CD-ROM) 2015 2015年
  • 上野 貢生, 孫 泉, 三澤 弘明 表面科学 35 (12) 668 -673 2014年12月 [査読無し][招待有り]
     
    We have successfully developed plasmon-induced water splitting system that operates under irradiation by visible light. Most important feature in this system is based on the use of both sides of the same strontium titanate (SrTiO3) single-crystal substrate without an electric wire connecting the anode and the cathode. The water splitting was induced, even with a minimum chemical bias of 0.23 V due to plasmonic effects based on the efficient water oxidation. Furthermore, we succeeded in visualizing the local field distribution of the localized surface plasmon resonance (LSPR) on gold nanoparticles and elucidating the dynamics of the LSPR by a time-resolved photoemission electron microscopy.
  • V. Ramamurthy, Hiroaki Misawa, Ken Ghiggino, Noboru Kitamura JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 20 III -IV 2014年09月 [査読無し][通常論文]
  • 局在表面プラズモンによる水の可視光分解
    上野 貢生, 三澤 弘明 光学 43 (6) 275 -277 2014年06月 [査読無し][招待有り]
  • 上野 貢生, 三澤 弘明 化學工業 65 (3) 189 -193 2014年03月 [査読無し][通常論文]
  • 可視光局在プラスモンの人工光合成への展開
    上野 貢生, 三澤 弘明 化学工業 65 (3) 21 -25 2014年03月 [査読無し][招待有り]
  • 上野貢生, 上野貢生, 伊藤弘子, 中野和佳子, 野澤翔, SUN Quan, 三澤弘明 応用物理学会春季学術講演会講演予稿集(CD-ROM) 61st 2014年
  • 押切友也, 上野貢生, 三澤弘明 日本化学会講演予稿集 94th (2) 2014年
  • 中村圭佑, 鎌田義臣, SHI Xu, 押切友也, 上野貢生, 三澤弘明 日本化学会講演予稿集 94th (2) 2014年
  • 上原日和, 押切友也, 上野貢生, 三澤弘明 日本化学会講演予稿集 94th (2) 2014年
  • 市川陽一, 上野貢生, 三澤弘明, 岡本裕巳, 岡本裕巳, 井村考平 日本分光学会年次講演会 2014 2014年
  • 野澤翔, 上野貢生, 三澤弘明, MAZHOROVA Anna, CLERICI Matteo, RAZZARI Luca, MORANDOTTI Roberto 日本化学会講演予稿集 94th (3) 2014年
  • 常盤塁也, SUN Quan, 上野貢生, 三澤弘明 応用物理学会春季学術講演会講演予稿集(CD-ROM) 61st 2014年
  • 溝端秀聡, 上野貢生, 三澤弘明, 岡本裕巳, 岡本裕巳, 井村考平 応用物理学会秋季学術講演会講演予稿集(CD-ROM) 75th 2014年
  • 中村圭佑, 押切友也, 上野貢生, 三澤弘明 光化学討論会要旨集(CD-ROM) 2014 2014年
  • 野澤翔, 上野貢生, 三澤弘明 光化学討論会要旨集(CD-ROM) 2014 2014年
  • 常盤塁也, SUN Quan, 上野貢生, 三澤弘明 光化学討論会要旨集(CD-ROM) 2014 2014年
  • 押切友也, 上野貢生, 三澤弘明 光化学討論会要旨集(CD-ROM) 2014 2014年
  • 上原日和, 押切友也, 上野貢生, 三澤弘明 光化学討論会要旨集(CD-ROM) 2014 2014年
  • 市川陽一, 上野貢生, 三澤弘明, 岡本裕巳, 岡本裕巳, 井村考平 分子科学討論会講演プログラム&要旨(Web) 8th 2014年
  • Yukie Yokota, Quan Sun, Kosei Ueno, Yasutaka Matuo, Hiroaki Misawa, Takuo Tanaka JSAP-OSA Joint Symposia 2014 Abstracts 2014年 [査読有り][通常論文]
  • 三澤 弘明 日本写真学会誌 76 (6) 444 -452 2014年01月 [査読無し][招待有り]
  • 光と物質を強く相互作用させる革新的光化学反応場の創出 懐中電灯で分子にレーザー並みの光強度を感じさせる方法論
    三澤 弘明 化学と工業 66 (8) 639 -641 2013年08月 [査読無し][招待有り]
  • 渡部愛理, 小竹勇己, 近松彰, 近松彰, 廣瀬靖, 廣瀬靖, 廣瀬靖, 上野貢生, 長谷川哲也, 長谷川哲也, 長谷川哲也, 三澤弘明 応用物理学会春季学術講演会講演予稿集(CD-ROM) 60th 2013年
  • 上野貢生, 上野貢生, 小竹勇己, SHI Xu, 三澤弘明 応用物理学会春季学術講演会講演予稿集(CD-ROM) 60th 2013年
  • 鎌田義臣, 小竹勇己, 上野貢生, 三澤弘明 日本化学会講演予稿集 93rd (2) 2013年
  • 野澤翔, 伊藤弘子, 中野和佳子, 上野貢生, 三澤弘明 日本化学会講演予稿集 93rd (3) 2013年
  • 松塚祐貴, OLIVIER Lecarme, 上野貢生, 三澤弘明 日本化学会講演予稿集 93rd (3) 2013年
  • 市川陽一, 今枝佳祐, 上野貢生, 三澤弘明, 岡本裕巳, 岡本裕巳, 井村考平 日本化学会講演予稿集 93rd (2) 2013年
  • 中村圭佑, 鎌田義臣, 押切友也, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2013 2013年
  • 上原日和, 押切友也, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2013 2013年
  • 上野貢生, 上野貢生, 伊藤弘子, 中野和佳子, 野澤翔, 三澤弘明 光化学討論会講演要旨集 2013 2013年
  • 鎌田義臣, 押切友也, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2013 2013年
  • 押切友也, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2013 2013年
  • 松塚祐貴, LECARME Olivier, SUN Quan, 押切友也, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2013 2013年
  • 常盤塁也, SUN Quan, 上野貢生, 上野貢生, 三澤弘明 応用物理学会春季学術講演会講演予稿集(CD-ROM) 60th 2013年
  • 東海林竜也, 柴田路子, 喜多村昇, 高瀬舞, 村越敬, 西島喜明, 上野貢生, 三澤弘明, 水元義彦, 石原一, 坪井泰之, 坪井泰之 日本化学会講演予稿集 92nd (2) 258 2012年03月09日 [査読無し][通常論文]
  • 砂山美里, 笠間康次, 荒木良子, 安倍真澄, 孫凱, LI Zheyu, 上野貢生, 三澤弘明 NIRS-M (National Inst. of Radiological Sciences) (247) 2012年
  • 竹田祥平, WANG Li, 西島喜明, 上野貢生, 三澤弘明, 玉井尚登 日本化学会講演予稿集 92nd (2) 2012年
  • 三澤弘明, SHI Xu, SUN Quan, SUN Quan, 小竹勇己, 上野貢生, 上野貢生 光化学討論会講演要旨集 2012 2012年
  • 上野貢生, 上野貢生, 伊藤弘子, 中野和佳子, 矢座寛人, 野澤翔, SUN Quan, SUN Quan, 三澤弘明 光化学討論会講演要旨集 2012 2012年
  • 上野貢生, 三澤弘明 CSJ Current Review (9) 2012年
  • 松塚祐貴, 上野貢生, 上野貢生, SUN Quan, SUN Quan, 三澤弘明 光化学討論会講演要旨集 2012 2012年
  • 矢座寛人, 伊藤弘子, 中野和佳子, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2012 2012年
  • 野澤翔, 伊藤弘子, 中野和佳子, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2012 2012年
  • 小竹勇己, SHI Xu, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2012 2012年
  • 砂山美里, 笠間康次, 荒木良子, 安倍真澄, 孫凱, LI Zheyu, 上野貢生, 三澤弘明 NIRS-M (National Inst. of Radiological Sciences) (249) 2012年
  • 常盤塁也, SUN Quan, SUN Quan, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2012 2012年
  • 井村考平, 井村考平, 今枝佳祐, 上野貢生, 上野貢生, 三澤弘明, 岡本裕巳 分子科学討論会講演プログラム&要旨(Web) 6th 2012年
  • LI Hao, 中治光童, 木場隆之, 木場隆之, 五十嵐誠, 寒川誠二, 寒川誠二, 佐久間実緒, 上野貢生, 三澤弘明, 村山明宏, 村山明宏 応用物理学会学術講演会講演予稿集(CD-ROM) 73rd 2012年
  • 日本縦断研究室巡り 北海道大学 電子科学研究所 三澤研究室
    三澤 弘明 レーザ協会誌 37 (1) 44 -47 2012年01月 [査読無し][招待有り]
  • プラズモニクスと光化学反応
    三澤 弘明 応用物理 80 (9) 766 -771 2011年09月 [査読無し][招待有り]
  • Shuyan Gao, Kosei Ueno, Hiroaki Misawa ACCOUNTS OF CHEMICAL RESEARCH 44 (4) 251 -260 2011年04月 [査読無し][招待有り]
     
    Efficient solar energy conversion has been vigorously pursued since the 1970s, but its large-scale implementation hinges on the availability of high-efficiency modules. For maximum efficiency, it is important to absorb most of the incoming radiation, which necessitates both efficient photoexcitation and minimal electron hole recombination. To date, researchers have primarily focused on the latter difficulty: finding a strategy to effectively separate photoinduced electrons and holes. Very few reports have been devoted to broadband sunlight absorption and photoexdtation. However, the currently available photovoltaic cells, such as amorphous silicon, and even single-crystal silicon and sensitized solar cells, cannot respond to the wide range of the solar spectrum. The photoelectric conversion characteristics of solar cells generally decrease in the infrared wavelength range. Thus, the fraction of the solar spectrum absorbed is relatively poor. In addition, the large mismatch between the diffraction limit of light and the absorption cross-section makes the probability of interactions between photons and cell materials quite low, which greatly limits photoexcitation efficiency. Therefore, there is a pressing need for research aimed at finding conditions that lead to highly efficient photoexdtation over a wide spectrum of sunlight, particularly in the visible to near-infrared wavelengths. As characterized in the emerging field of plasmonics, metallic nanostructures are endowed with optical antenna effects. These plasmonic antenna effects provide a promising platform for artificially sidestepping the diffraction limit of light and strongly enhancing absorption cross-sections. Moreover, they can efficiently excite photochemical reactions between photons and molecules dose to an optical antenna through the local field enhancement. This technology has the potential to induce highly efficient photoexcitation between photons and molecules over a wide spectrum of sunlight, from visible to near-infrared wavelengths. In this Account, we describe our recent work in using metallic nanostructures to assist photochemical reactions for augmenting photoexcitation efficiency. These studies investigate the optical antenna effects of coupled plasmonic gold nanoblocks, which were fabricated with electron-beam lithography and a lift-off technique to afford high resolution and nanometric accuracy. The two-photon photoluminescence of gold and the resulting nonlinear photopolymerization on gold nanoblocks substantiate the existence of enhanced optical field domains. Local two-photon photochemical reactions due to weak incoherent light sources were identified. The optical antenna effects support the unprecedented realization of (i) direct photocarrier injection from the gold nanorods into TiO(2) and ID) efficient and stable photocurrent generation in the absence of electron donors from visible (450 nm) to near-infrared (1300 nm) wavelengths.
  • 北翔太, 大塚翔太, 羽中田祥司, 遠藤達郎, 西島喜明, 三澤弘明, 馬場俊彦 応用物理学関係連合講演会講演予稿集(CD-ROM) 58th ROMBUNNO.25P-KA-1 2011年03月09日 [査読無し][通常論文]
  • 広がるプラズモニクス研究(巻頭言)
    三澤 弘明 光学 40 (2) 67 -67 2011年02月 [査読無し][招待有り]
  • 中治光童, 木場隆之, 木場隆之, 村山明宏, 村山明宏, 佐久間実緒, 横田幸恵, 上野貢生, 三澤弘明 応用物理学関係連合講演会講演予稿集(CD-ROM) 58th 2011年
  • 西島喜明, 村澤尚樹, 上野貢生, 椎屋由紀子, 米澤孝枝, 堀田祐司, 三澤弘明 応用物理学関係連合講演会講演予稿集(CD-ROM) 58th 2011年
  • 西島喜明, 上野貢生, 三澤弘明 日本化学会講演予稿集 91st (2) 2011年
  • 小竹勇己, 西島喜明, 上野貢生, 三澤弘明 日本化学会講演予稿集 91st (3) 2011年
  • 西島喜明, 上野貢生, 上野貢生, 小竹勇己, 村越敬, 井上晴夫, 三澤弘明 光化学討論会講演要旨集 2011 2011年
  • 岡崎健一, 安井淳一, 大木信, 村澤尚樹, 上野貢生, 三澤弘明, 鳥本司 光化学討論会講演要旨集 2011 2011年
  • 青陽大輔, 上野貢生, 上野貢生, 小竹勇己, 三澤弘明 光化学討論会講演要旨集 2011 2011年
  • 小竹勇己, 西島喜明, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2011 2011年
  • 武藤将充, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2011 2011年
  • 中谷光博, 小竹勇己, 青陽大輔, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2011 2011年
  • 上野貢生, 上野貢生, 大西広, 伊藤弘子, 三澤弘明 光化学討論会講演要旨集 2011 2011年
  • 青陽大輔, 村澤尚樹, 西島喜明, 上野貢生, 三澤弘明 日本化学会講演予稿集 91st (3) 2011年
  • 旭秀典, SUN Quan, 上野貢生, 上野貢生, 三澤弘明 光化学討論会講演要旨集 2011 2011年
  • 横田幸恵, WANG Li, 上野貢生, QIU Jian-rong, 三澤弘明 日本化学会講演予稿集 91st (3) 2011年
  • 井村考平, 井村考平, 上野貢生, 上野貢生, 三澤弘明, 岡本裕巳 分子科学討論会講演プログラム&要旨(Web) 5th 2011年
  • 中治光童, 木場隆之, 木場隆之, 村山明宏, 村山明宏, 佐久間実緒, 横田幸恵, 上野貢生, 三澤弘明 応用物理学会学術講演会講演予稿集(CD-ROM) 72nd 2011年
  • Kosei Ueno, Hiroaki Misawa Photochemistry 39 228 -255 2011年 [査読無し][通常論文]
     
    The global problems relevant to the environment and energy are attracting attention, so that it is considered that the construction of efficient lightenergy conversion devices serves as an important subject of the scientific research. Thus far, the interaction between photons and molecules has not received much attention in photochemistry. However, the creation of a progressive methodology that allows an increase in the excitation probability is necessary because the photochemical reaction begins with light absorption process. Namely, to create a low-carbon-emitting society by utilizing light energy, it is necessary to introduce the concept of "effective utilization of photons" to photochemistry. In this chapter, the significance of the development of photochemical reaction fields, in which make it possible to increase the interaction between photons and molecules, is described. Metallic nanostructures showing localized surface plasmon resonance are a promising approach for the development of photochemical reaction fields. As an outstanding feature of our photochemical reaction fields, we have verified two-photon photopolymerization of negative photoresists on the closely spaced gold nanoparticles irradiated by a weak incoherent light source. We also demonstrated the efficient plasmonic photoelectric conversion by near-infrared light using electrodes, in which gold nanoblocks were elaborately arrayed on the surface of a titanium dioxide single-crystal. © The Royal Society of Chemistry 2011.
  • 井村考平, 井村考平, 上野貢生, 上野貢生, 三澤弘明, 岡本裕巳 分子科学討論会講演プログラム&要旨(Web) 5th ROMBUNNO.4B12 (WEB ONLY) 2011年 [査読無し][通常論文]
  • 田中嘉人, 石黒裕康, 藤原英樹, 上野貢生, 三澤弘明, 笹木敬司 Optics & Photonics Japan講演予稿集(CD-ROM) 2011 ROMBUNNO.P39 2011年 [査読無し][通常論文]
  • 石黒裕康, 田中嘉人, 藤原英樹, 藤原英樹, 横田幸恵, 上野貢生, 上野貢生, 三澤弘明, 笹木敬司 応用物理学会学術講演会講演予稿集(CD-ROM) 71st ROMBUNNO.17A-NJ-8 2010年08月30日 [査読無し][通常論文]
  • 北翔太, 大塚翔太, 羽中田祥司, 遠藤達郎, 西島喜明, 三澤弘明, 馬場俊彦 応用物理学会学術講演会講演予稿集(CD-ROM) 71st ROMBUNNO.15A-ZW-18 2010年08月30日 [査読無し][通常論文]
  • 金属ナノ構造を用いた光局在場の創成と光化学反応への応用
    上野貢生, 三澤 弘明 触媒 52 (3) 166 -171 2010年04月 [査読無し][招待有り]
  • 田中嘉人, 石黒裕康, 藤原英樹, 藤原英樹, 横田幸恵, 上野貢生, 上野貢生, 三澤弘明, 笹木敬司 応用物理学関係連合講演会講演予稿集(CD-ROM) 57th ROMBUNNO.18A-P4-8 2010年03月03日 [査読無し][通常論文]
  • 光と分子が強く結合するナノ空間の創成
    上野 貢生, 三澤 弘明 化学 65 (4) 22 -27 2010年03月 [査読無し][招待有り]
  • 荒木剛, 西島喜明, 村澤尚樹, 上野貢生, 上野貢生, 西井準治, 三澤弘明 応用物理学関係連合講演会講演予稿集(CD-ROM) 57th 2010年
  • 村澤尚樹, 青陽大輔, 上野貢生, 三澤弘明 応用物理学関係連合講演会講演予稿集(CD-ROM) 57th 2010年
  • 上野貢生, 上野貢生, 三澤弘明 応用物理学関係連合講演会講演予稿集(CD-ROM) 57th 2010年
  • 横田幸恵, 上野貢生, 上野貢生, 三澤弘明 応用物理学関係連合講演会講演予稿集(CD-ROM) 57th 2010年
  • 西島喜明, 上野貢生, 上野貢生, 横田幸恵, 村越敬, 三澤弘明 応用物理学関係連合講演会講演予稿集(CD-ROM) 57th 2010年
  • 青陽大輔, 村澤尚樹, 上野貢生, 横田幸恵, 三澤弘明 日本化学会講演予稿集 90th (3) 2010年
  • 横田幸恵, 上野貢生, 三澤弘明 日本化学会講演予稿集 90th (3) 2010年
  • 池谷伸太郎, 上野貢生, 村澤尚樹, 三澤弘明 日本化学会講演予稿集 90th (3) 2010年
  • 西島喜明, 上野貢生, 村越敬, 三澤弘明 日本化学会講演予稿集 90th (3) 2010年
  • 上野貢生, WU Botao, 横田幸恵, 三澤弘明 光化学討論会講演要旨集 2010 2010年
  • 辻剛志, 上野貢生, 横田幸恵, 辻正治, 三澤弘明 光化学討論会講演要旨集 2010 2010年
  • 吉田裕, 谷津茂男, 渡辺精一, 西島喜明, 上野貢生, 三澤弘明, 加藤隆彦 日本金属学会講演概要 147th 2010年
  • 横田幸恵, WANG Li, 上野貢生, 上野貢生, QIU Jian-rong, 三澤弘明 光化学討論会講演要旨集 2010 2010年
  • 旭秀典, SUN Quan, 西島喜明, 村澤尚樹, 上野貢生, 上野貢生, 三澤弘明 応用物理学関係連合講演会講演予稿集(CD-ROM) 57th 2010年
  • 吉田裕, 谷津茂男, 渡辺精一, 西島喜明, 上野貢生, 三澤弘明, 加藤隆彦 応用物理学会学術講演会講演予稿集(CD-ROM) 71st 2010年
  • 蝦名渉, 西島喜明, MIZEIKIS Vygantas, 上野貢生, 西井準治, 三澤弘明 日本化学会講演予稿集 90th (3) 2010年
  • 荒木剛, 村澤尚樹, 上野貢生, 横田幸恵, 西島喜明, 西井準治, 三澤弘明 日本化学会講演予稿集 90th (3) 2010年
  • 玉井尚登, 王莉, 西島喜明, 上野貢生, 三澤弘明, 新留康朗 分子科学討論会講演プログラム&要旨(Web) 4th 2010年
  • 治田将, 三澤弘明, 上野貢生, 横田幸恵, 西井準治, 田和圭子, 奥津哲夫, 奥津哲夫 光化学討論会講演要旨集 2010 2010年
  • 治田将, 三澤弘明, 上野貢生, 西井準治, 横田幸恵, 山下卓勇, 奥津哲夫 日本化学会講演予稿集 90th (2) 2010年
  • 原田洋介, 井村考平, 岡本裕巳, 西島喜明, 上野貢生, 三澤弘明, 長瀬和也, 大西大 エクストリームフォトニクス研究 第11回 理研・分子研合同シンポジウム 平成22年 161 -162 2010年 [査読無し][通常論文]
  • 原田洋介, 井村考平, 井村考平, 岡本裕巳, 西島喜明, 上野貢生, 三澤弘明, 長瀬和也, 大西大 分子科学討論会講演プログラム&要旨(Web) 4th ROMBUNNO.4P061 (WEB ONLY) 2010年 [査読無し][通常論文]
  • 友田 基信, 松枝 真之介, Wright Oliver B, 松田 理, 西島 善明, 上野 貢生, Saulius Juodkazis, 三澤 弘明 超音波エレクトロニクスの基礎と応用に関するシンポジウム講演論文集 30 457 -458 2009年11月18日 [査読無し][通常論文]
  • 局在プラズモンを利用した非線形光化学
    上野貢生, 三澤弘明 機能材料 29 6 -13 2009年11月 [査読無し][招待有り]
  • Hiroaki Misawa, Donald A. Tryk, Hiroshi Masuhara JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 207 (1) 1 -3 2009年09月 [査読無し][通常論文]
  • Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa JOURNAL OF APPLIED PHYSICS 106 (5) 051101 2009年09月 [査読無し][通常論文]
     
    Femtosecond laser fabrication of three-dimensional structures for photonics applications is reviewed. Fabrication of photonic crystal structures by direct laser writing and holographic recording by multiple beam interference techniques are discussed. The physical mechanisms associated with structure formation and postfabrication are described. The advantages and limitations of various femtosecond laser microfabrication techniques for the preparation of photonic crystals and elements of microelectromechanical and micro-optofluidic systems are discussed.
  • 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 日本化学会講演予稿集 89th (1) 2009年
  • 池谷伸太郎, 上野貢生, 村澤尚樹, 西島喜明, 横田幸恵, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2009 2009年
  • WANG Li, 西島喜明, 横田幸恵, 上野貢生, JUODKAZIS Saulius, 三澤弘明, 麦野遥一, 大西大, QIU Jian-rong 応用物理学会学術講演会講演予稿集 70th (3) 2009年
  • 横田幸恵, 上野貢生, 上野貢生, JUODKAZIS Saulius, 三澤弘明 応用物理学会学術講演会講演予稿集 70th (3) 2009年
  • 池谷伸太郎, 上野貢生, 上野貢生, 村澤尚樹, 西島喜明, 横田幸恵, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 応用物理学会学術講演会講演予稿集 70th (3) 2009年
  • 村澤尚樹, 青陽大輔, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2009 2009年
  • 西島喜明, 上野貢生, JUODKAZIS Saulius, 村越敬, 三澤弘明 光化学討論会講演要旨集 2009 2009年
  • 横田幸恵, 上野貢生, 上野貢生, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2009 2009年
  • 辻剛志, 上野貢生, 横田幸恵, 辻正治, 三澤弘明 固体・表面光化学討論会講演要旨集 28th 2009年
  • 三澤弘明, JUODKAZIS Saulius, MIZEIKIS Vygantas, SUN Quan, 上野貢生, 高畠聡章 高分子学会予稿集(CD-ROM) 58 (2 Disk1) 2009年
  • 三澤弘明, 上野貢生, ヨードカジス サウリウス SORSTシンポジウム2 講演要旨集 フレクシブルデバイス/マテリアルの未来像 平成21年 2009年
  • 高畠聡章, 上野貢生, 西島喜明, SUN Kai, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2009 2009年
  • 蝦名渉, 西島喜明, MIZEIKIS Vygantas, 上野貢生, JUODKAZIS Saulius, 三澤弘明 応用物理学会学術講演会講演予稿集 70th (3) 2009年
  • 上野貢生, 上野貢生, 高畠聡章, 西島喜明, SUN Kai, MIZEKIS Vygantas, JUODKAZSI Saulius, 三澤弘明 応用物理学関係連合講演会講演予稿集 56th (3) 2009年
  • 高畠聡章, 上野貢生, 西島善明, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 日本化学会講演予稿集 89th (1) 2009年
  • 治田将, 上野貢生, 横田幸恵, 三澤弘明, 奥津哲夫 結晶成長国内会議予稿集 39th 2009年
  • 治田将, 上野貢生, 横田幸恵, 三澤弘明, 奥津哲夫 光化学討論会講演要旨集 2009 2009年
  • フェムト秒レーザによる微細加工技術
    三澤 弘明 電子材料 48 (2) 80 -87 2009年 [査読無し][招待有り]
  • 金属ナノ構造による光局在場の創製と非線形光化学反応への応用
    上野貢生, 三澤弘明 化学工業 60 (10) 737 -742 2009年 [査読無し][招待有り]
  • プラズモン増強場の形成と光反応
    上野貢生, 三澤弘明 光学 38 (9) 448 -455 2009年 [査読無し][招待有り]
  • Danworaphong Sorasak, Kelf Timothy A, 松田 理, Wright Oliver B, 上野 貢生, 西島 喜明, Juodkazis Saulius, 三澤 弘明 超音波エレクトロニクスの基礎と応用に関するシンポジウム講演論文集 29 179 -180 2008年11月11日 [査読無し][通常論文]
  • 友田 基信, Wright Oliver B, 上野 貢生, 西島 喜明, Juodkazis Saulius, 三澤 弘明 超音波エレクトロニクスの基礎と応用に関するシンポジウム講演論文集 29 377 -378 2008年11月11日 [査読無し][通常論文]
  • 井村考平, 岡本裕巳, 上野貢生, 三澤弘明 応用物理学会学術講演会講演予稿集 69th (3) 901 2008年09月02日 [査読無し][通常論文]
  • Etienne Brasselet, Naoki Murazawa, Saulius Juodkazis, Hiroaki Misawa PHYSICAL REVIEW E 77 (4) 041704 2008年04月 [査読無し][通常論文]
     
    Laser manipulation of trapped radial 4(')-n-pentyl-4-cyanobiphenyl (5CB) nematic liquid-crystal droplets induced by molecular reordering is presented. We show experimentally that optical tweezers having linear, elliptical, or circular polarization can break the radial symmetry of the initial molecular organization inside a radial nematic droplet. Static distorted or twisted deformation modes and steady or unsteady nonlinear rotational dynamics are observed. Statics results are analyzed in terms of light-induced radial or left-right symmetry breaking effects associated with optical reorientation. The dynamical observations are compared with simulations from a slab analog model, for which orientational processes driven by optical nonlinearities can be accurately described. This study confirms that light-induced bulk reordering is an essential ingredient towards the understanding of the behavior of radial nematic liquid-crystal droplets in laser tweezers, as suggested by previous studies.
  • Saulius Juodkazis, Vygantas Mizeikis, Shigeki Matsuo, Kosei Ueno, Hiroaki Misawa BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 81 (4) 411 -448 2008年04月 [査読無し][通常論文]
     
    Three-dimensional laser microfabrication blends microscopy, optical nonlinear phenomena, photomodification, laser trapping, and creates novel possibilities for fabrication of micro- and nano-structures in a wide range of materials. This work reviews various implementations of laser photo-structuring and micromanipulation applied to photo-modification of various materials: glasses, crystals, polymers, gels, and liquid crystals.
  • 井村考平, 岡本裕巳, 上野貢生, 三澤弘明 応用物理学関係連合講演会講演予稿集 55th (3) 1082 2008年03月27日 [査読無し][通常論文]
  • 西島喜明, 上野貢生, JUODKAZIS Saulius, MIZEIKIS Vygantas, 三澤弘明, 前田暢, 皆木正司 日本化学会北海道支部研究発表会講演要旨集 2008 2008年
  • 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 日本化学会北海道支部研究発表会講演要旨集 2008 2008年
  • 三野雅弘, 上野貢生, 大西大, 坂口拓生, 麦野遙一, ミゼイキス ビガンタス, ヨードカジス サウリウス, 三澤弘明 日本化学会北海道支部研究発表会講演要旨集 2008 2008年
  • 村澤尚樹, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 日本化学会講演予稿集 88th (1) 2008年
  • 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 日本化学会講演予稿集 88th (1) 2008年
  • 宮本博徹, 上野貢生, 大西大, 坂口拓生, 麦野遥一, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2008 2008年
  • 池谷伸太郎, 上野貢生, 横田幸恵, 西島喜明, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2008 2008年
  • 西島喜明, 上野貢生, JUODKAZIS Saulius, MIZEIKIS Vygantas, 三澤弘明, 前田暢, 皆木正司 日本化学会講演予稿集 88th (1) 2008年
  • 村澤尚樹, 上野貢生, MIZEKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2008 2008年
  • 高畠聡章, 上野貢生, 西島喜明, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2008 2008年
  • 高畠聡章, 上野貢生, ヨードカジス サウリウス, 三澤弘明, 日野敦司 日本化学会北海道支部研究発表会講演要旨集 2008 2008年
  • 上野貢生, 高畠聡章, MIZEIKIS Vygantas, SAULIUS Juodkazis, 三澤弘明 日本化学会講演予稿集 88th (1) 2008年
  • 高畠聡章, 上野貢生, 上野貢生, 西島喜明, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 応用物理学会学術講演会講演予稿集 69th (3) 2008年
  • 神成謙太, JUODKAZIS Saulius, MIZEIKIS Vygantas, 上野貢生, 三澤弘明 高分子学会北海道支部研究発表会講演要旨集 42nd 2008年
  • 高木睦, 北林孝之, 小泉覚, 廣瀬遙香, 藤原政司, 上野貢生, 三澤弘明, 細川陽一郎, 増原宏, 脇谷滋之 再生医療 7 2008年
  • 岡本裕巳, 井村考平, キム スイル, キム スイル, 上野貢生, 三澤弘明 分子科学討論会講演プログラム&要旨(Web) 2nd ROMBUNNO.1B19 (WEB ONLY) 2008年 [査読無し][通常論文]
  • 井村考平, 岡本裕巳, 上野貢生, 三澤弘明 分子科学討論会講演プログラム&要旨(Web) 2nd ROMBUNNO.1B18 (WEB ONLY) 2008年 [査読無し][通常論文]
  • 高木 睦, 酒井 純, 上野 貢生, 三澤 弘明, 細川 陽一郎, 増原 宏 日本生物工学会大会講演要旨集 20 87 -87 2008年 [査読無し][通常論文]
  • Saulius Juodkazis, Vygantas Mizeikis, Toshiaki Kondo, Kenta Kannari, Kock Khuen Seet, Hiroaki Misawa Proceedings of SPIE - The International Society for Optical Engineering 6883 2008年 [査読無し][通常論文]
     
    Three-dimensional (3D) structuring of polymers by tightly focused femtosecond laser pulses and interference is demonstrated. Photo-structuring by the tightly focused sub-1 ps laser pulses realizes a direct laser writing inside dielectric materials without self-focusing. Photo-polymerization of 3D photonic crystal templates with photonic stop bands in IR-spoctral region has been achieved. Holographic photo-polymerization of photonic crystal templates with counter-propagating beams was numerically modeled. Three-dimensional structures with an axial period smaller than the lateral can be recorded using the counter-propagating beam alignment. Photopolymerization of large-area polymeric structures with a high surface-to-volume ratio is demonstrated.
  • 半導体加工技術により作製した金属ナノ構造による新しいフォトニック材料
    上野貢生, 三澤弘明 未来材料 (1) 14 -21 2008年01月 [査読無し][招待有り]
  • レーザでウエハ切断
    三澤 弘明 レーザ加工学会誌 15 (2) 126 -127 2008年 [査読無し][招待有り]
  • 光の時代における光化学
    三澤 弘明 光化学 39 (2) 65 -65 2008年 [査読無し][招待有り]
  • 高木 睦, 北林 孝之, 小泉 覚, 上野 貢生, 三澤 弘明, 細川 陽一郎, 増原 宏, 脇谷 滋之, 藤原 政司 日本生物工学会大会講演要旨集 平成19年度 139 -139 2007年08月 [査読無し][通常論文]
  • 村澤尚樹, 三澤弘明 高分子 56 (7) 510 -510 2007年07月 [査読無し][招待有り]
  • 高畠聡章, 上野貢生, JUODKAZIS Saulius, 三澤弘明, 日野敦司 光化学討論会講演要旨集 2007 2007年
  • 上野貢生, 三野雅弘, 大西大, 坂口拓生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 日本化学会講演予稿集 87th (1) 2007年
  • 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 笹木敬司, 三澤弘明 日本化学会講演予稿集 87th (1) 2007年
  • 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2007 2007年
  • 上野貢生, 澁谷俊志, 横田幸恵, VYGANTAS Mizeikis, SAULIUS Juodkazis, 笹木敬司, 三澤弘明 分析化学討論会講演要旨集 68th 2007年
  • 井村考平, 岡本裕巳, 上野貢生, 三澤弘明 分子科学討論会講演要旨集(CD-ROM) 1st 2007年
  • 横田幸恵, 横田幸恵, 上野貢生, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三澤弘明, 三澤弘明 日本化学会北海道支部研究発表会講演要旨集 2007 2007年
  • 西島喜明, 上野貢生, JUODKAZIS Saulius, MIZEIKIS Vygantas, 三澤弘明, 谷村敏博, 前田浩平 光化学討論会講演要旨集 2007 2007年
  • 村澤尚樹, 上野貢生, 渋谷俊志, 横田幸恵, MIZEIKIS Vygantas, JUODKAZIS Saulius, 笹木敬司, 三澤弘明 応用物理学会学術講演会講演予稿集 68th (3) 2007年
  • 上野貢生, 大西大, 三野雅弘, 坂口拓生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三澤弘明 応用物理学会学術講演会講演予稿集 68th (3) 2007年
  • 西島喜明, 上野貢生, MIZEIKIS Vygantas, 三澤弘明, 谷村敏博, 前田浩平 日本化学会講演予稿集 87th (1) 2007年
  • 三野雅弘, 上野貢生, 大西大, 坂口拓生, VYGANTAS Mizeikis, JUODKAZIS Saulius, 三澤弘明 光化学討論会講演要旨集 2007 2007年
  • 井村考平, 岡本裕巳, 上野貢生, 三澤弘明 エクストリームフォトニクス研究-バイオイメージング 第5回理研・分子研合同シンポジウム 平成19年 2007年
  • 高橋友美, 上野貢生, 西島喜明, 三澤弘明, 谷村敏博, 前田浩平 日本化学会北海道支部研究発表会講演要旨集 2007 2007年
  • 渋谷俊志, 渋谷俊志, 上野貢生, 上野貢生, 横田幸恵, 横田幸恵, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三澤弘明, 三澤弘明 日本化学会北海道支部研究発表会講演要旨集 2007 2007年
  • 三澤弘明, 上野貢生, JUODKAZIS Saulius, MIZEIKIS Vygantas 高分子学会予稿集(CD-ROM) 56 (2 Disk1) 2007年
  • 西島喜明, 上野貢生, 藤原英樹, 三澤弘明, 笹木敬司, 谷村敏博, 前田浩平, MIZEIKIS Vygantas, JUODKAZIS Saulius 粉体工学会夏期シンポジウム講演論文集 43rd 68 -69 2007年 [査読無し][通常論文]
  • 高木 睦, 北林 孝之, 小泉 覚, 上野 貢生, 三澤 弘明, 細川 陽一郎, 増原 宏, 脇谷 滋之, 藤原 政司 化学工学会 研究発表講演要旨集 2007 (0) 719 -719 2007年 [査読無し][通常論文]
  • フェムト秒レーザによるサファイア基板の3次元加工
    三澤 弘明 レーザー加工学会誌 14 (1) 42 -44 2007年 [査読無し][招待有り]
  • 北海道における光産業の可能性
    三澤 弘明 開発こうほう 525 24 -25 2007年 [査読無し][招待有り]
  • 松尾繁樹, 富田卓朗, 橋本修一, 岡田達也, ヨードカシスサウリウス, 三澤弘明 レーザー学会研究会報告 = Reports on the Topical meeting of the Laser Society of Japan 356 47 -51 2006年12月11日 [査読無し][通常論文]
  • 松尾繁樹, 三澤弘明 日本結晶成長学会誌 33 (4) 254 -255 2006年11月01日 [査読無し][通常論文]
     
    Colloid crystallization by a method similar to the graphoepitaxy is described. In this method, V-shaped pits and grooves with specific angles are used for the crystallization of colloid particles; such the pits and grooves can be fabricated by anisotropic etching of silicon substrates. This method has the advantages of ease of fabrication, and diameter-free. The experimental results on this method are presented.
  • 西島喜明, 上野貢生, 藤原英樹, 笹木敬司, 三澤弘明, 谷村敏博, 前田浩平 応用物理学会学術講演会講演予稿集 67th (3) 953 2006年08月29日 [査読無し][通常論文]
  • フェムト秒レーザーを利用した単一接着細胞の遺伝子発現解析
    北林 孝之, 上野 貢生, 三澤 弘明, 細川 陽一郎, 増原 宏, 脇谷 滋之, 藤原 政司, 高木 睦 日本生物工学会大会講演要旨集 平成18年度 191 -191 2006年08月 [査読無し][通常論文]
  • S. Juodkazis, E. Gaizauskas, V. Jarutis, J. Reif, S. Matsuo, H. Misawa Journal of Physics D: Applied Physics 39 (14) 1 2006年07月21日 [査読無し][通常論文]
  • Hiroaki Misawa, Saulius Juodkazis 3D Laser Microfabrication: Principles and Applications 1 -4 2006年06月29日 [査読無し][通常論文]
  • Hiroaki Misawa, Saulius Juodkazis 3D Laser Microfabrication: Principles and Applications 1 -388 2006年06月29日 [査読無し][通常論文]
     
    A thorough introduction to 3D laser microfabrication technology, leading readers from the fundamentals and theory to its various potent applications, such as the generation of tiny objects or three-dimensional structures within the bulk of transparent materials. The book also presents new theoretical material on dielectric breakdown, allowing a better understanding of the differences between optical damage on surfaces and inside the bulk, as well as a look into the future. Chemists, physicists, materials scientists and engineers will find this a valuable source of interdisciplinary knowledge in the field of laser optics and nanotechnology. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA.
  • Vygantas Mizeikis, Shigeki Matsuo, Saulius Juodkazis, Hiroaki Misawa 3D Laser Microfabrication: Principles and Applications 239 -286 2006年06月29日 [査読無し][通常論文]
     
    The evolution of modern photonic technologies depends on the possibilities of obtaining large-scale photonic crystals cheaply and efficiently. Photonic crystals [1, 2] are periodic dielectric structures which are expected to play an important role in optics and optoelectronics due to their unique capability of controlling the emission and propagation of light via photonic band gap (PBG) and stop-gap effects. A comprehensive summary of the properties of various classes of PBG materials and their potential capabilities can be found in the literature, for example, books [3-6]. According to common knowledge, the wavelengths at which PBGs or stop-gaps open are close to the period of the dielectric lattice. At the same time, the most desirable spectral region for opto-electronic devices, including those based on photonic crystals, is in the visible and near-infrared wavelength range. Given this requirement, fabrication of structures periodic in one, two or three dimensions, and comprising many lattice periods, is not a trivial task. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA.
  • 三澤 弘明 レーザー研究 34 (5) 340 -340 2006年05月15日
  • パルスレーザによる透明材料の三次元加工 ーバイオマテリアルなどのナノ加工も視野にー
    三澤 弘明 Semiconductor FPD World 5 82 -85 2006年05月 [査読無し][招待有り]
  • 三澤 弘明 レーザー学会誌 34 (5) 341 -345 2006年05月 [査読無し][招待有り]
  • 上野貢生, 上野貢生, VYGANTAS Mizeikis, SAULIUS Juodkazis, SAULIUS Juodkazis, 笹木敬司, 笹木敬司, 三澤弘明, 三澤弘明 分析化学討論会講演要旨集 67th 2006年
  • WANG Huaishan, 上野貢生, JUODKAZIS Saulius, JUODKAZIS Saulius, 三澤弘明, 三澤弘明 光化学討論会講演要旨集 2006 2006年
  • 岡田陽平, 上野貢生, 横田幸恵, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三澤弘明, 三澤弘明 光化学討論会講演要旨集 2006 2006年
  • 渋谷俊志, 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三澤弘明, 三澤弘明 光化学討論会講演要旨集 2006 2006年
  • 三野雅弘, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三澤弘明, 三澤弘明 光化学討論会講演要旨集 2006 2006年
  • 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三沢弘明, 三沢弘明 応用物理学関係連合講演会講演予稿集 53rd (3) 2006年
  • 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 三澤弘明, 三澤弘明 光化学討論会講演要旨集 2006 2006年
  • 宇川広訓, 上野貢生, 三澤弘明, 喜多村昇 日本分析化学会年会講演要旨集 55th 2006年
  • 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三沢弘明, 三沢弘明 応用物理学関係連合講演会講演予稿集 53rd (3) 2006年
  • 上野貢生, 岡田陽平, 三野雅弘, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三澤弘明, 三澤弘明 応用物理学会学術講演会講演予稿集 67th (3) 2006年
  • 高橋友美, 上野貢生, 三澤弘明, 谷村敏博, 前田浩平 光化学討論会講演要旨集 2006 2006年
  • 西島喜明, 上野貢生, 高橋友美, VYGANTAS Mizeikis, 三澤弘明, 谷村敏博, 前田浩平 分析化学討論会講演要旨集 67th 2006年
  • 高橋友美, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三沢弘明, 谷村敏博, 前田浩平 応用物理学関係連合講演会講演予稿集 53rd (3) 2006年
  • 横田幸恵, 渋谷俊志, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三澤弘明, 三澤弘明 応用物理学会学術講演会講演予稿集 67th (3) 2006年
  • 陶山明史, 林田雅行, YE J.-Y., EDIGIUS Vanagas, 上野貢生, JUODKAZIS Saulius, JUODKAZIS Saulius, 三澤弘明, 三澤弘明, 日野敦司 光化学討論会講演要旨集 2006 2006年
  • 神成謙太, 神成謙太, 近藤敏明, SEET Kock Khuen, 松尾繁樹, 上野貢生, 上野貢生, JOUDKAZIS Saulius, JOUDKAZIS Saulius, 三澤弘明, 三澤弘明 応用物理学会学術講演会講演予稿集 67th (3) 2006年
  • 西島喜明, 上野貢生, 三澤弘明, 谷村敏博, 前田浩平 光化学討論会講演要旨集 2006 2006年
  • 超高密度フォトン束による固体の光反応制御
    三澤 弘明 日本化学会 アワードアカウンツ 2006年 [査読無し][通常論文]
  • 北大発ベンチャー 株式会社レーザーシステム
    三澤 弘明 「SEMI News」SEMI ジャパン 22 (4) 18 -19 2006年 [査読無し][招待有り]
  • 三野雅弘, 上野貢生, 林田雅行, 横田幸恵, MIZEIKIS Vygantas, JUODKAZIS Saulius, 三沢弘明 光化学討論会講演要旨集 2005 2005年
  • 上野貢生, 三野雅弘, 林田雅行, 横田幸恵, MIZEIKIS Vygantas, JAUDKAZIS Saulius, JAUDKAZIS Saulius, 三沢弘明, 三沢弘明 応用物理学会学術講演会講演予稿集 66th (3) 2005年
  • 上野貢生, 三野雅弘, 林田雅行, 林田雅行, 横田幸恵, 横田幸恵, MIZEIKIS Vygantas, JUOKAZIS Saulius, JUOKAZIS Saulius, 三沢弘明, 三沢弘明 日本分析化学会年会講演要旨集 54th 2005年
  • 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Sauliu, 笹木敬司, 三沢弘明 光化学討論会講演要旨集 2005 2005年
  • 宇川広訓, 岩田訓志, 上野貢生, 三沢弘明, 喜多村昇 分析化学討論会講演要旨集 66th 2005年
  • 上野貢生, MIZEIKIS Vygantas, 笹木敬司, 笹木敬司, 三沢弘明, 三沢弘明 分析化学討論会講演要旨集 66th 2005年
  • 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, JUODKAZIS Saulius, 笹木敬司, 笹木敬司, 三沢弘明, 三沢弘明 応用物理学会学術講演会講演予稿集 66th (3) 2005年
  • 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 笹木敬司, 三沢弘明 応用物理学関係連合講演会講演予稿集 52nd (3) 2005年
  • 宇川広訓, 岩田訓志, 上野貢生, 三沢弘明, 喜多村のぼる 日本化学会北海道支部研究発表会講演要旨集 2005 2005年
  • 横田幸恵, 上野貢生, MIZEIKIS Vygantas, JUODKAZIS Saulius, 笹木敬司, 三沢弘明 光化学討論会講演要旨集 2005 2005年
  • 宇川広訓, 上野貢生, 三沢弘明, 喜多村しょう 化学とマイクロ・ナノシステム研究会講演要旨集 12th(CD-ROM) 2005年
  • Saulius Juodkazis, Toshiaki Kondo, Hiroaki Misawa Pacific Rim Conference on Lasers and Electro-Optics, CLEO - Technical Digest 2005 1737 -1738 2005年 [査読無し][通常論文]
  • Saulius Juodkazis, Yuusuke Tabuchi, Takahiro Ebisui, Shigeki Matsuo, Hiroaki Misawa Proceedings of SPIE - The International Society for Optical Engineering 5850 59 -66 2005年 [査読無し][通常論文]
     
    Post-processing of crystalline and glass materials after the exposure to femtosecond pulses was carried out by wet etching in water solutions of hydrofluoric acid. Crystalline sapphire and quartz showed high (larger than 100) anisotropy of etching, which allowed to develop high-aspect-ratio three-dimensional structures in the volume of those dielectrics. In silicate glasses the anisotropy of wet etching can be achieved by a proper selection of the overlap of adjacent pulses during recording, their energy, and focusing. Three-dimensional structures in silica glass (viosil with OH concentration below 1200 ppm) with a high aspect ratio of 100 were achieved. The mechanism of anisotropy in wet etching is discussed. Surface irradiation of sapphire at irradiance close to that of surface ablation recorded structural modifications resembling the ripples. Those structures were made observable only after wet etching. Period of the ripples can be explained by the recently presented theory (Y. Shimotsuma et al., Phys. Rev. Lett. 91 247405-1 (2003)). Sub-micrometer structuring of surface is demonstrated. Electron temperature at the moment of structure recording can be estimated from the period of ripples (for sapphire Te ≃ 11 keV was found).
  • フェムト秒レーザープロセスによるフォトニック結晶の作製
    三澤 弘明 レーザ加工学会誌 12 (2) 8 -11 2005年 [査読無し][通常論文]
  • 三澤 弘明 真空 48 (9) 501 -505 2005年 [査読無し][通常論文]
  • フェムト秒レーザー加工
    三澤 弘明 ナノテクノロジー技術動向調査、未踏科学技術協会 35 -37 2005年 [査読無し][通常論文]
  • 北大発ベンチャー 株式会社レーザーシステム
    三澤 弘明 レーザー研究 33 (10) 692 -693 2005年 [査読無し][招待有り]
  • 三澤 弘明 表面技術 56 (12) 807 -811 2005年 [査読無し][招待有り]
  • 三澤 弘明, 上野 貢生 光化学 36 (2) 128 -134 2005年 [査読無し][招待有り]
  • 近藤敏明, SauliusJuodkazis, VygantasMizeikis, 松尾繁樹, 三澤弘明 年次大会講演論文集 : JSME annual meeting 2004 (4) 349 -350 2004年09月04日 [査読無し][通常論文]
     
    We report the method to fabricate micro-periodic structures using interference of femtosecond pulses (Wavelength 800nm; Pulse duration 150 femtosecond; Repetition Rate 1kHz). The method is based on pulse division using diffractive beam splitter and facilitates a spatio-temporal overlap of constituent pulslets. We demonstrate interference patterns formed by several pulslets and successful fabrication 1-, 2- and 3-dimensional micro periodic structures after a few minutes exposure of a commercial photosensitive resin (SU-8; Microlithography Chemical Corp.) with micrometer resolution.
  • 三澤弘明, 松尾繁樹 レーザ加工学会誌 11 (1) 46 -48 2004年04月 [査読無し][通常論文]
  • 松尾繁樹, 三澤弘明 レーザー研究 32 (2) 105 -109 2004年02月15日 [査読無し][通常論文]
  • 荒木武志, 上野貢生, 三沢弘明, 喜多村昇 日本分析化学会年会講演要旨集 53rd 2004年
  • 岩田訓志, 上野貢生, 池田美和子, 須藤康夫, 内田達也, 藤原き多夫, 三沢弘明, 喜多村のぼる 化学とマイクロ・ナノシステム研究会講演要旨集 10th 2004年
  • 松尾繁樹, 三澤弘明 高温学会誌 30 (2) 77 -81 2004年 [査読無し][通常論文]
  • 光ナノプロセス技術
    三澤 弘明 光学 33 (11) 645 -650 2004年 [査読無し][通常論文]
  • フェムト秒パルスレーザー加工
    三澤 弘明 OPTRONICS 4 131 -136 2004年 [査読無し][通常論文]
  • レーザー光による分子マニピュレ—ション
    三澤 弘明 レーザ加工学会誌 11 (1) 7 -11 2004年 [査読無し][通常論文]
  • 第7回日米先端科学シンポジウム
    三澤 弘明 レーザ加工学会誌 11 (1) 7 -11 2004年 [査読無し][通常論文]
  • Kai Sun, Shigeki Matsuo, Hiroaki Misawa 2003 Nanotechnology Conference and Trade Show - Nanotech 2003 1 86 -89 2003年12月01日 [査読無し][通常論文]
     
    A transparent microchannel chip for continuous-flow polymerase chain reaction (PCR) was developed. The microchannel was fabricated on a cover glass substrate using standard photolithography and wet-etching techniques, and sealed by another cover glass substrate. A heat source consisting of two indium-tin-oxide (ITO) films was deposited on the etched substrate. An insulation layer of SiO 2 was then deposited on the ITO heaters. Thin, patterned ITO films deposited on the insulation layer served as temperature sensors. Linear relationship between the thin ITO film sheet resistivity and the temperature was confirmed and calibrated. An amplication of a 97-bp segment of rat tongue cDNA was successfully performed with the chip.
  • 三澤弘明, 松尾繁樹 高分子 52 (10) 754 -757 2003年10月01日 [査読無し][通常論文]
     
    フォトニック結晶は,光集積回路や超低しきい値レーザーに応用することが可能であり,現在,さまざまな分野で活発な研究が進められている。筆者らは,シリコン基板上に作製したテンプレート中で高分子微粒子をfcc構造に配列させて3次元フォトニック結晶を作製することに成功した。本稿ではその作製法とその将来展望について述べる。
  • 三澤弘明, 松尾繁樹, JuodkazisSaulius, MizeikisVygantas, 福田晃一, 近藤敏彰, 藤根貴富 電子情報通信学会ソサイエティ大会講演論文集 2003 (1) "S -11"-"S-12" 2003年09月10日 [査読無し][通常論文]
  • 奥野紘規, 松尾繁樹, ヨードカシスサウリウス, 三澤弘明 年次大会講演論文集 : JSME annual meeting 2003 (4) 311 -312 2003年08月05日 [査読無し][通常論文]
     
    It has been established that femtosecond pulse laser is a useful tool for direct microfablication of solid materials. We investigate micro-drilling of the small and deep holes into stainless steel plates with femtosecond laser pulses. We have adjusted beam diameter and focus length of lens, which determines the diameter of laser beam at the focus, and obtained holes with 180μm diameter by using an objective lens of 31mm focus length and 4mm beam diameter. But it isn't deep enough to utilize in many industrial applications. For making much deeper holes, we have demonstrated laser-scanning ab...
  • 村澤尚樹, 松尾繁樹, JuodkazisSaulius, 三澤弘明 年次大会講演資料集 3 (3) 193 -194 2003年08月05日 [査読無し][通常論文]
  • 近藤敏彰, JuodkazisSaulius, MizeikisVygantas, 松尾繁樹, 三澤弘明 年次大会講演資料集 3 (3) 195 -196 2003年08月05日 [査読無し][通常論文]
  • 山崎和彦, JuodokazisSaulius, 戎井嵩裕, 田淵祐介, 松尾繁樹, 三澤弘明 年次大会講演資料集 3 (3) 197 -198 2003年08月05日 [査読無し][通常論文]
  • 松尾繁樹, JarutisVygandas, MizeikisVygantas, JuodkazisSaulius, 三澤弘明 年次大会講演資料集 3 (3) 199 -200 2003年08月05日 [査読無し][通常論文]
  • 孫凱, 崔平, 松尾繁樹, 木戸博, 三澤弘明 電子情報通信学会技術研究報告. MBE, MEとバイオサイバネティックス 103 (184) 1 -4 2003年07月06日 [査読無し][通常論文]
     
    透明材料を用いてヒーターとセンサー一体型のマイクロリアクターを作製し,定量ポリメラーゼチェインリアクション(PCR)を行った。光りソグラフィー技術,ウェットエッチング技術によりガラス基板にマイクロチャンネルを加工し,マイクロチャンネル基板上に形成したITOフィルムに電圧を印加することによりマイクロリアクターの温度コントロールを行った。顕微鏡とICCDのカメラシステムはSYBR^[○!R] Green Iを使用して、dsDNAの蓄積を検知するために使用されました。作製したマイクロリアクターを用いてマウスの舌cDNAからX遺伝子をテンプレートとしたPCRを行ったところ,塩基数97のPCR生成物を確認した。
  • 林田雅行, 劉洪春, 山口央, 松尾繁樹, 三澤弘明 電子情報通信学会技術研究報告. MBE, MEとバイオサイバネティックス 103 (184) 5 -8 2003年07月06日 [査読無し][通常論文]
     
    表面プラズモン共鳴(SPR)イメージング測定はDNAマイクロアレイにおけるハイブリダイゼーション検出手法として有望視されているが、DNAハイブリダイゼーションによるSPR応答は微小であり、検出感度、精度の向上のためにSPR信号の増幅が必要である。これまでに我々はプローブDNA末端に金微粒子を修飾することにより、空気中のSPR測定においてハイブリダイゼーション前後でSPR信号が増大されることを明らかとしてきた。今回、溶液中での金微粒子修飾DNA単分子膜によるハイブリダイゼーションの検出を行い、溶液中においてもSPR信号が増幅されることを確認した。
  • 松尾繁樹, 三澤弘明 O plus E 25 (2) 158 -163 2003年02月 [査読無し][通常論文]
  • A Marcinkevicius, Mizeikis, V, S Juodkazis, S Matsuo, H Misawa APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 76 (2) 257 -260 2003年02月 [査読無し][通常論文]
     
    We studied the peculiarities of femtosecond laser microfabrication in silica glass with a refractive index that did not exactly match the value for which the focusing optics is designed. Spherical aberrations resulting from a small refractive index mismatch were found to increase the size and distort the shape of photodamaged regions, thus reducing the spatial resolution of the microfabrication. However, these undesirable effects can be minimized, providing that the focusing depth inside the glass is not too large, and the laser intensity is kept close to the light-induced damage threshold.
  • 高木均, 田倉隆輝, 一原洋平, 越智真治, 三沢弘明, 仁木龍祐 材料 52 (4) 353 -356 2003年 [査読無し][通常論文]
     
    In recent years there has been an increasing interest in using natural fibers as reinforcements for biodegradable plastics from the environment-friendly viewpoint. In this study the mechanical properties of bamboo fibers extracted by a steam-explosion method has been investigated by means of the tensile test. From the experimental results it was found that the tensile strength of bamboo fibers depended on the steam-explosion conditions and that the strength of the bamboo fibers extracted at relatively low temperatures and for a short period was high but the scattering of the strength also became large, thus optimum steam-explosion conditions were at 190°C for 1.8 - 3.6ks. Finally we found that the tensile strength of bamboo fiber extracted by the steam-explosion method was larger than that of bamboo fiber cut out from a raw bamboo indicating the steam-explosion is suitable extraction method for bamboo fibers. In addition, the tensile strength of bamboo fibers also depended on their height sampled. The bamboo fibers sampled from relatively high position had low tensile strength and these weak fibers were not suitable as reinforcements for high-strength composites.
  • O. Efimov, S. Juodkazis, S. Matsuo, H. Misawa OSA Trends in Optics and Photonics Series 88 1201 -1202 2003年01月01日 [査読無し][通常論文]
     
    We show that the mechanism of the glass laser-induced damage involves a collective response of the dielectric, rather than the individual generation of electrons, and that modification of medium precedes the plasma formation under fs-pulses. ? 2000 Optical Society of America.
  • Akihiro Takita, Hirotsugu Yamamoto, Yoshio Hayasaki, Nobuo Nishida, Mitsuru Watanabe, Shigeki Matsuo, Hiroaki Misawa Proceedings of SPIE - The International Society for Optical Engineering 4829 1104 -1105 2003年 [査読無し][通常論文]
     
    Optical data storage in nails using a femtosecond laser system is demonstrated. A bit is formed as a structural change of the nail by irradiation of a femtosecond laser pulse. The recorded bit is observed using a conventional microscope. The size of the bit increases with increasing irradiation pulse energy. The pulse energy necessary to form a bit depends on the recording depth and the surface condition of the nail.
  • Saulius Juodkazis, Toshiaki Kondo, Slava Dubikovski, Vygantas Mizeikis, Shigeki Matsuo, Hiroaki Misawa Proceedings of SPIE - The International Society for Optical Engineering 5147 226 -235 2003年 [査読無し][通常論文]
     
    We demonstrate fabrication of two-dimensional (2D) photonic crystal (PhC) structure inside the volume of SU-8 resist film by four beams interference. This structure, actually, is a 3D structure fabricated inside the film without sample scanning or laser beam steering. The mechanism of recording iii transparent dielectrics is discussed in terms of third harmonic generation, white light continuum, and thermal omission by "hot" electrons.
  • Toshiaki Kondo, Shigeki Matsuo, Saulius Juodkazis, Vygantas Mizeikis, Hiroaki Misawa Journal of Photopolymer Science and Technology 16 (3) 427 -432 2003年 [査読無し][通常論文]
     
    Fabrication and characteristics of two-dimensional (2D) and three-dimensional (3D) periodic structures, recorded inside the bulk of negative SU8 photoresist film by multiple-beam interference are reported. The recording was performed by ultrashort laser pulses of 150 fs duration with central wavelength of 800 nm, multiple beams were generated using a diffractive beam splitter. Intensity-dependent photomodification of the photoresist was initiated by multi-photon absorption. The development process removed the exposed regions of resist film, leaving free-standing 2D and 3D periodic dielectric structures. Detailed examination of the samples is presented, which reveals close resemblance between the features of the fabricated structures, and those of the light intensity distributions in the multiple-beam interference fields. The microfabrication method used is demonstrated to be suitable for obtaining of photonic crystal templates. Phase control of the constituent beams allowed to monitor and control the light interference pattern to be recorded. Possibility to record the diamond lattice using this method is examined and discussed.
  • フェムト秒レーザーによる三次元超加工
    三澤 弘明 機能材料 23 (2) 44 -51 2003年 [査読無し][通常論文]
  • 光圧による分子マニピュレ—ション
    三澤 弘明 応用物理 72 (6) 716 -720 2003年 [査読無し][通常論文]
  • 三澤弘明, 松尾繁樹 精密工学会誌 68 (11) 1393 -1397 2002年11月05日 [査読無し][通常論文]
  • JY Ye, Mizeikis, V, Y Xu, S Matsuo, H Misawa OPTICS COMMUNICATIONS 211 (1-6) 205 -213 2002年10月 [査読無し][通常論文]
     
    We report on the fabrication and properties of quasi-two-dimensional photonic crystals (Phcs) with honeycomb lattices of dielectric rods in air. Photonic crystals, fabricated in silicon by electron beam lithography and dry-etching techniques, had the high aspect ratio of 12, corresponding to a rod height of about 7 mum. The optical transmission spectra of the samples measured in the 1.8-8 mum wavelength range, revealed pronounced features of photonic band dispersion, and a signature of a complete photonic band gap (PBG) centered at 2.3 mum wavelength. (C) 2002 Elsevier Science B.V. All rights reserved.
  • A Yamaguchi, P Jin, H Tsuchiyama, T Masuda, K Sun, S Matsuo, H Misawa ANALYTICA CHIMICA ACTA 468 (1) 143 -152 2002年09月 [査読無し][通常論文]
     
    Applicability of polydimethylsiloxane (PDMS) for easy and rapid fabrication of enzyme sensor chips, based on electrochemical detection, is examined. The sensor chip consists of PDMS substrate with a microfluidic channel fabricated in it, and a glass substrate with enzyme-modified microelectrodes. The two substrates are clamped together between plastic plates. The sensor chip has shown no leakage around the microelectrodes under continuous solution flow (34 mul/min). Amperometric response of the sensor chips developed in this work suggest that various types of enzyme sensors can be designed by using PDMS microfluidic channels. (C) 2002 Elsevier Science B.V. All rights reserved.
  • A Yamaguchi, P Jin, H Tsuchiyama, T Masuda, K Sun, S Matsuo, H Misawa ANALYTICA CHIMICA ACTA 468 (1) 143 -152 2002年09月 [査読無し][通常論文]
     
    Applicability of polydimethylsiloxane (PDMS) for easy and rapid fabrication of enzyme sensor chips, based on electrochemical detection, is examined. The sensor chip consists of PDMS substrate with a microfluidic channel fabricated in it, and a glass substrate with enzyme-modified microelectrodes. The two substrates are clamped together between plastic plates. The sensor chip has shown no leakage around the microelectrodes under continuous solution flow (34 mul/min). Amperometric response of the sensor chips developed in this work suggest that various types of enzyme sensors can be designed by using PDMS microfluidic channels. (C) 2002 Elsevier Science B.V. All rights reserved.
  • 松尾繁樹, 三澤弘明 光技術コンタクト 40 (8) 480 -489 2002年08月 [査読無し][通常論文]
  • T Takasone, S Juodkazis, Y Kawagishi, A Yamaguchi, S Matsuo, H Sakakibara, H Nakayama, H Misawa JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 41 (5A) 3015 -3019 2002年05月 [査読無し][通常論文]
     
    Microtubules, which are flexible biopolymers, can be used for nanotechnology applications (e.g., nano-actuator) as they have a rigidity similar to that of plexyglass and other plastic materials. The flexural rigidity, or bending stiffness, of microtubules was measured using a laser trapping technique and dark-field microscopy. One end of a microtubule rod was chemically bound to a glass microsphere, while the other end was bound to a silica glass substrate. Then, the microsphere was laser-trapped and manipulated to exert three different deformation modes on the microtubule. The values of flexural rigidity for these deformations were between 10(-25) and 10(-23) Nm(2) as measured for the 5-25 mum length microtubules. The origin of the length dependence of the flexural rigidity of microtubules is discussed.
  • S Matsuo, H Misawa REVIEW OF SCIENTIFIC INSTRUMENTS 73 (5) 2011 -2015 2002年05月 [査読無し][通常論文]
     
    For many laser applications, information on irradiated laser power is important. However, direct measurement of laser power through a high numerical aperture objective lens is difficult in a laser microscope. In this article, we propose a method which use a solid immersion lens (SIL) for such measurements. A laser beam focused by an objective lens is introduced to the flat surface of a SIL, emitted through the spherical surface, and then detected. In this way the divergence of the laser beam is reduced, and as a result the detection efficiency of the laser power increases. From theoretical analysis, a Weierstrass-sphere type SIL was found to be an appropriate thickness for this propose. Transmittance of the SIL is evaluated for several refractive indeces. The validity of this method is confirmed experimentally. (C) 2002 American Institute of Physics.
  • 山口央, 土山博史, 松尾繁樹, 横山順一, 三澤弘明 電気学会論文誌. E, センサ・マイクロマシン準部門誌 = The transactions of the Institute of Electrical Engineers of Japan. A publication of Sensors and Micromachines Society 122 (3) 172 -178 2002年03月01日 [査読無し][通常論文]
     
    Several bonding techniques for the development of microchannel chip at room temperature were studied. An electrostatic interaction between poly-ion layers with opposite charge and a condensation of silane coupling agent was employed to bond two glass substrates. In former case, the bonding of the substrates was achieved by applying high electrical potential. On the other hand, the condensation of silane coupling agent could bond the two glass substrates at room temperature and atmosphere. It was confirmed that the microchannel developed using the silane coupling agent could work for flow channel without solution leak. Poly(dimethylsiloxane)(PDMS) substrate was also applied for chip development. As a result, it was confirmed that PDMS was a material for easy and rapid fabrication of microchannel chip integrated with film electrodes
  • S Juodkazis, K Fujiwara, T Takahashi, S Matsuo, H Misawa JOURNAL OF APPLIED PHYSICS 91 (3) 916 -921 2002年02月 [査読無し][通常論文]
     
    We report a morphology-dependent resonance (MDR) laser emission of rhodamine-doped ellipsoidal microcavity of the poly(methylmethacrylate) particles. Elliptical particles showed different lasing properties: the lasing threshold, intramode spectral separation, mode intensity, and spectral position, when an excitation is pointed to the different locations on the particle. This differs from the well-understood MDR lasing in spherical microparticles. (C) 2002 American Institute of Physics.
  • A Yamaguchi, S Juodkazis, S Matsuo, H Misawa CHEMISTRY LETTERS 190-191 (2) 190 -191 2002年02月 [査読無し][通常論文]
     
    In this study, we demonstrate that the Au particle modified probe DNA monolayer can enhance the surface plasmon resonance (SPR) signal for measuring hybridization of unlabeled DNA molecules. The Au particles adsorbed on single stranded (ss)- and double stranded (ds)-DNA monolayers have different optical interaction with surface of Au thin film, and this difference induces the enhancement of the SPR signal.
  • 服部武, 羽場方紀, 藤井利宣, 増田隆夫, 三沢弘明, 細田幸子, 上野貢生, 喜多村のぼる 日本分析化学会年会講演要旨集 51st 2002年
  • 三澤 弘明 レーザー学会学術講演会年次大会講演予稿集 = Annual meeting of the Laser Society of Japan digest of technical papers 22 S4 -S5 2002年01月01日
  • Toru Takasone, Saulius Juodkazis, Shigeki Matsuo, Akira Yamaguchi, Keiji Sasaki, Jun-Ichi Hotta, Hiroaki Misawa Proceedings of SPIE - The International Society for Optical Engineering 4830 212 -217 2002年 [査読無し][通常論文]
     
    We demonstrate a few examples of laser trapping and manipulation technique being applied for the measurements of small forces in the range of fN-pN and for laser microfabrication. We discuss prospective principles applicable for future nano/micro-mechanical tools. Elastic properties of microtubules of 24 nm in diameter were determined, a gold particle of 0.25 μm in diameter was laser trapped and manipulated. Paramagnetic microspheres were DNA-anchored to a glass substrate for measurement of elastic properties of DNA by evanescent light scattering. Also, a gold particle was attached to DNA and laser manipulated. The motion of the DNA molecule was controlled. The spring constant of the DNA was determined by using thermodynamical analysis of evanescent light scattering.
  • Saulius Juodkazis, Makoto Horyama, Masafumi Miwa, Mitsuru Watanabe, Andrius Marcinkevičius, Vygantas Mizeikis, Shigeki Matsuo, Hiroaki Misawa Proceedings of SPIE - The International Society for Optical Engineering 4644 27 -38 2002年 [査読無し][通常論文]
     
    We review applications of photopolymerization and photodamage by tightly focused picosecond and femtosecond pulses for the formation of three-dimensional structures. Laser microfabrication of various structures, like surface gratings, 3D optical memory, 2D and 3D photonic crystals, 3D micro-fluidic systems, etc. are described. Microfabrication by laser irradiation provides new opportunities to realize microstructures and microdevices, highly demanded in a number of fields, e.g., microchemistry, information storage, and photonics. The background of this technique is very simple, and relies on modification of materials by intense, strongly focused laser irradiation. In this highly spatially localized region, the material may become destroyed, solidified from liquid, or otherwise photo-modified, and complex structures can be formed from many photomodified regions. Below, we describe techniques, applications, and achievements of laser microstructuring in liquid resins and solid silica glasses.
  • Dielectric Breakdown of Rubber Material by Femtosecond Irradiation (共著)
    Appl.Phys. A 75 1 -5 2002年 [査読無し][通常論文]
  • Development of Microchannel Chip Using Chemical Bonding Techniques at Room Temperature (共著)
    Trans. IEE of Japan 122-E 172 -177 2002年 [査読無し][通常論文]
  • A Heater-Integrated Transparent Microchannel Chip for Continuous-Flow PCR(共著)
    Sesors & Actuators, B:Chem 4229 1 -7 2002年 [査読無し][通常論文]
  • 放射圧の科学的応用に関する研究からフェムト秒超加工、そして量子リソグラフィーへの展開
    三澤 弘明 O plus E 一枚の写真 1183 -1184 2002年 [査読無し][通常論文]
  • 次世代遺伝子解析マイクロアレイの開発
    三澤 弘明 STEPねっとわーく 8 (2) 10 -11 2002年 [査読無し][通常論文]
  • 高密度フォトンと物質との相互作用
    三澤 弘明 花王ケミカルだより (51) 15 -15 2002年 [査読無し][招待有り]
  • V. Mizeikis, S. Juodkazis, A. Marcinkevicius, H. B. Sun, T. Kondo, S. Matsuo, H. Misawa Pacific Rim Conference on Lasers and Electro-Optics, CLEO - Technical Digest 1 2001年12月01日 [査読無し][通常論文]
     
    Microfabrication of photonic crystal (PhC) structures in silica glass and photopolymerizing resins using femtosecond lasers was presented. The structural and photonic characteristics of microfabricated photonic crystal structures were also investigated. The PhC structures fabricated in silica glass and resins showed high structural quality and revealed moderate photonic pseudogaps. It was observed that using materials with higher refractive index, full bandgaps can be achieved.
  • Akihiro Takita, Hirotsugu Yamamoto, Yoshio Hayasaki, Nobuo Nishida, Mitsuru Watanabe, Shigeki Matsuo, Hiroaki Misawa Pacific Rim Conference on Lasers and Electro-Optics, CLEO - Technical Digest 1 2001年12月01日 [査読無し][通常論文]
     
    The demonstration of three-dimensional optical recording inside nail using femtosecond pulse laser was presented. Bit arrays were recorded inside nail to demonstrate three-dimensional optical storage. The relations between irradiation pulse and bit size were investigated. The presence of threshold of irradiation pulse energy for bit recording inside nail was shown by the investigations.
  • 早崎芳夫, 田北啓洋, 渡辺満, 山本裕紹, 松尾繁樹, 三澤弘明, 西田信夫 電子情報通信学会技術研究報告. LQE, レーザ・量子エレクトロニクス 101 (452) 7 -10 2001年11月15日 [査読無し][通常論文]
     
    高い安全性を有する新しい情報の携帯を実現するために, 爪内部へのビット情報の記録をフェムト秒レーザー加工技術を用いて実現する.ます, 照射エネルギーと記録されるビットのサイズの関係を示す.さらに, 記録の表面からの深さを深くすると, 表面の粗さの影響で, 記録に必要な照射エネルギーが増大することを示す.さらに, レーザー共焦点顕微鏡を用いたビット情報の再生結果を示す.
  • Hiroyuki Sugimura, Takayuki Hanji, Osamu Takai, Takao Masuda, Hiroaki Misawa Electrochimica Acta 47 (1) 103 -107 2001年09月01日 [査読無し][通常論文]
     
    Micropatterning of organosilane self-assembled monolayers (SAMs) was demonstrated on the basis of photolithography using an excimer lamp radiating vacuum ultraviolet light of 172 nm wavelength. This lithography is generally applicable to micropatterning of organic thin films including alkylsilane SAMs, since its patterning mechanism involves cleavage of C-C bonds in organic molecules and subsequent decomposition of the molecules. In this study, SAMs were prepared on Si substrates covered with native oxide by chemical vapor deposition in which an alkylsilane, that is, octadecyltrimethoxysilane [CH3(CH2)17Si(OCH3)3, ODS] was used as a precursor. SAM was photoirradiated through a photomask placed on its surface so that it was decomposed and removed in the photoirradiated area while the masked areas remained undecomposed. Accordingly, the photomask image was printed on the SAM as a removed/unremoved pattern. The patterned SAM could be used as a mask for plasma etching or area-selective Ni electroless plating. © 2001 Elsevier Science Ltd. All rights reserved.
  • T Kondo, S Matsuo, S Juodkazis, H Misawa APPLIED PHYSICS LETTERS 79 (6) 725 -727 2001年08月 [査読無し][通常論文]
     
    A simple optical interference method to fabricate microperiodic structures was demonstrated. Femtosecond laser pulse was split by a diffractive beam splitter and overlapped with two lenses. Temporal overlap of the split femtosecond pulses, which requires 10 mum order accuracy in optical path lengths, was automatically achieved by this optical setup. One-, two-, and three-dimensional periodic microstructures with micrometer-order periods were fabricated using this method. (C) 2001 American Institute of Physics.
  • Y Xu, HB Sun, JY Ye, S Matsuo, H Misawa JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS 18 (8) 1084 -1091 2001年08月 [査読無し][通常論文]
     
    We report the fabrication and characterization of two-dimensional silicon-based photonic crystal (PhC) structures realized by a combination of electron-beam lithography and dry-etching techniques. PhCs of various lattices with very high aspect ratios up to 20 have been achieved, and PhC chips were prepared by standard semiconductor technologies, including thinning and cleaving. The chips consisting of high-aspect-ratio air rods or dielectric rods permit a direct transmission measurement, and they were observed to demonstrate pronounced photonic bandgap effects. Several photonic bandgap behaviors were identified by comparing transmission with reflection and experimental results with numerical results, and by considering detecting beam property. (C) 2001 Optical Society of America.
  • V. Mizeikis, S. Juodkazis, A. Marcinkevičius, S. Matsuo, H. Misawa Journal of Photochemistry and Photobiology C: Photochemistry Reviews 2 (1) 35 -69 2001年07月17日 [査読無し][通常論文]
     
    Photonic crystals are promising systems for application in the fields of optoelectronics and optical communications. Understanding of their underlying physical principles and techniques for fabrication and characterization has progressed significantly during the last decade. This paper outlines the main achievements in these areas, and gives an overview of various photonic crystal systems, including those fabricated in semiconductors by traditional tools of microelectronics, and those fabricated from glasses, resins and other materials using novel non-traditional techniques. © 2001 Japanese Photochemistry Association.
  • 原洋一郎, 山口央, 松尾繁樹, 三澤弘明 電子情報通信学会技術研究報告. MBE, MEとバイオサイバネティックス 101 (182) 93 -99 2001年07月07日 [査読無し][通常論文]
     
    表面プラズモン共鳴(SPR)分光法は金属薄膜表面に化学修飾した一本鎖プローブDNA分子に対する検体DNA分子のハイブリダイゼーションをin-situ(その場)観測するために適した手法である。しかし, DNA分子のハイブリダイゼーションによるSPR信号変化は小さく, SPR信号の増幅は検出感度・精度を向上させる上で必要不可欠である。本研究では, DNAハイブリダイゼーション検出に用いるための金薄膜基板作製条件について検討するとともに, SPR信号僧服を目的に金薄膜表面に固定化したプローブDNA末端に金ナノ微粒子を修飾した。その結果, 金ナノ微粒子修飾によりハイブリダイゼーションに伴うSPR信号の増幅が観測された。
  • 孫凱, 山口央, 石田豊, 大井文香, 松尾繁樹, 三澤弘明 電子情報通信学会技術研究報告. MBE, MEとバイオサイバネティックス 101 (182) 101 -106 2001年07月07日 [査読無し][通常論文]
     
    透明材料を用いてヒーター一体型のマイクロリアクターを作製し, ポリメラーゼチェインリアクション(PCR)を行った。光リソグラフィー技術, ウェットエッチング技術により石英基板にマイクロチャンネルを加工し, マイクロチャンネル基板上に形成したITOフィルムに電圧を印加することによりマイクロリアクターの温度コントロールを行った。ピレンスルホン酸(PS-Na)の蛍光スペクトルを計測することによりマイクロリアクター内の溶液温度をモニターしたところ, PCRのための温度サイクルをITOフィルムにより制御可能であることが明らかとなった。作製したマイクロリアクターを用いて大腸菌株のHB101をテンプレートとしたPCRを行ったところ, 塩基数450のPCR生成物を確認した。
  • 山口央, 土山博史, 金鵬, 松尾繁樹, 三澤弘明 電子情報通信学会技術研究報告. MBE, MEとバイオサイバネティックス 101 (182) 107 -113 2001年07月07日 [査読無し][通常論文]
     
    シリコーンゴムの一種であるポリジメチルシロキサン(PDMS)は鋳型を用いて簡便にマイクロチャンネルを加工することが可能であり、ガラスやプラスチック基板などにより室温でマイクロチャンネルに蓋をすることが出来ることから、集積化マイクロチップを作製するための素材として注目を集めている。本研究はPDMSを用いて迅速かつ簡便にマイクロ酵素センサーを作成する方法の開発を目的とした。ガラス基板上に金フィルム電極を加工し、マイクロチャンネルを加工したPDMS基板と張り合わせたところ、チャンネルからの溶液リークは観測されず、安定的な電気化学応答が観測された。また、酵素を電極表面に修飾することにより酵素センサーとして動作することを確認した。
  • HB Sun, Mizeikis, V, Y Xu, S Juodkazis, JY Ye, S Matsuo, H Misawa APPLIED PHYSICS LETTERS 79 (1) 1 -3 2001年07月 [査読無し][通常論文]
     
    We report the fabrication and characteristics of planar microcavities in a log-pile photonic crystal structure formed using light-induced photopolymerization of resin. A planar defect was introduced into the middle of the log-pile structure as a single layer with every second rod missing. The existence of confined cavity states was confirmed experimentally and by numeric simulations. The cavity resonance found at the midgap wavelength lambda (M)similar to4.0 mum had a quality factor of about 130. (C) 2001 American Institute of Physics.
  • P Jin, A Yamaguchi, FA Oi, S Matsuo, JB Tan, H Misawa ANALYTICAL SCIENCES 17 (7) 841 -846 2001年07月 [査読無し][通常論文]
     
    A micro glucose sensor consisting of an interdigitated array gold microelectrode was developed. The interdigitated array structure, which has 10 mum band width and 10 mum band gap, was fabricated in a small region (2.5 x 5 mm(2)) on a quartz substrate. Glucose oxidase was chemically fixed onto the electrode surface through self-assembled monolayer of 11-mercaptoundecanoic acid; ferroceneacetic acid was used as electron mediator. Electrochemical properties of the glucose oxidase-immobilized microelectrode were investigated by cyclic voltammogram measurements. Results confirmed that the reductive ferroceneacetic acid generated at counter electrode diffuses through a narrow band gap (10 mum) and can reach the working electrode surface.
  • S Juodkazis, A Yamaguchi, H Ishii, S Matsuo, H Takagi, H Misawa JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 40 (6A) 4246 -4251 2001年06月 [査読無し][通常論文]
     
    We report the patterning of Pt on a TiO2-rutile single crystal (the fundamental absorption band starts at 396 nm) by direct deposition from a water solution of H2PtCl6 (10-20 mmol/dm(3)) using laser beam writing at 390-396 nm, or by Hg-lamp illumination (i-line at 365 nm). Pt deposition was corroborated by microchemical analysis. A resolution of the Pt patterning down to 20-30 nm was achieved. To create a Pt pattern with resolution of twenty nanometers. we employed a mask elaborated with electron-beam (EB) drawing lithography. The mask was transparent to the writing illumination. The Pt was reduced from the solution by laser beam scanning over resist-covered regions, while the pattern was formed in the openings of the resist. Separation of the growth and illumination regions, typically, by 0.5-2 mum, facilitates the deposition of reproducible, high-aspect-ratio patterns. It is demonstrated that Pt was deposited through a process of diffusion of the light-excited carriers. The possibility of fabrication of a three-dimensional Pt pattern by the overgrowth of the resist is discussed.
  • 松尾繁樹, 三澤弘明 日本結晶成長学会誌 28 (1) 25 -30 2001年03月26日 [査読無し][通常論文]
     
    The mainstream of fabrication of photonic crystals is inorganic semiconductor techniques. Organic photonic crystals are not major, but possess unique and attracting futures. In this review, we introduce fabrication techniques of organic photonic crystals such as microsphere segmentation, laser microfabrication and laser interference fabrication. The advantage of microsphere segmentation is simple process to make micro periodicity, while that of laser microfabrication is high freedom of designing the photonic crystals. Characteristic applications of organic photonic crystals are also mention...
  • HB Sun, Y Xu, S Juodkazis, K Sun, M Watanabe, S Matsuo, H Misawa, J Nishii OPTICS LETTERS 26 (6) 325 -327 2001年03月 [査読無し][通常論文]
     
    We used voxels of an intensely modified refractive index generated by multiphoton absorption at the focus of femtosecond laser pulses in Ge-doped silica as photonic atoms to build photonic lattices. The voxels were spatially organized in the same way as atoms arrayed in actual crystals, and a Bragg-like diffraction from the photonic atoms was evidenced by a photonic bandgap (PBG) effect Postfabrication annealing was found to be essential for reducing random scattering and therefore enhancing PEG. This technique has an intrinsic capability of individually addressing single atoms. Therefore the introduction of defect structures was much facilitated, making the technique quite appealing for photonic research and applications. (C) 2001 Optical Society of America.
  • A Marcinkevicius, S Juodkazis, M Watanabe, M Miwa, S Matsuo, H Misawa, J Nishii OPTICS LETTERS 26 (5) 277 -279 2001年03月 [査読無し][通常論文]
     
    We demonstrate direct three-dimensional (3-D) microfabrication inside a volume of silica glass. The whole fabrication process was carried out in two steps: (i) writing of the preprogrammed 3-D pattern inside silica glass by focused femtosecond (fs) laser pulses and (ii) etching of the written structure in a 5% aqueous solution of HF acid. This technique allows fabrication of 3-D channels as small as 10 mum in diameter inside the volume with any angle of interconnection and a high aspect ratio (10-mum-diameter channels in a 100-mum-thick silica slab). (C) 2001 Optical Society of America.
  • 三澤 弘明 レーザー学会学術講演会年次大会講演予稿集 = Annual meeting, of the Laser Society of Japan digest of technical papers 21 129 -130 2001年01月01日
  • 三澤 弘明 徳島大学工学部研究報告 46 57 -63 2001年
  • Saulius Juodkazis, Y. Arisawa, S. Matsuo, H. Misawa, R. Tomasiunas, J. Vaitkus Proceedings of SPIE-The International Society for Optical Engineering 4318 42 -47 2001年 [査読無し][通常論文]
     
    Optimization of (i) intensity of illumination and (ii) thickness of resist was made looking for the conditions when high spatial resolution could be achieved by optical near-field lithography. Standard set-up of near-field illumination through a tapered Al-coated fiber tip was employed for the exposure of positive resist OFPR-5000(EG), which is photo-sensitive for wavelength λ < 450 nm. Tip was scanned along the line at near-field conditions of constant sample-to-tip separation to produce adjustable exposure dose of the spin-coated resist film. Femtosecond, 120 fs, pulses of the power P < 1 mW (at 82 MHz repetition rate) at 400 nm were coupled into a fiber (< 1 m length) and delivered to the surface of the resist for illumination.The issues of NSOM fabrication using tapered Al-coated tips are addressed. To achieve a reproducible and high aspect ratio (approaching 1: 1) NSOM-based lithography there should be found resists allowing to produce thin films (< 100 nm) with low surface roughness (< 10 nm).
  • 三澤 弘明 レーザー研究 30 (5) 239 -243 2001年 [査読無し][通常論文]
  • 多光子吸収による光化学反応の空間制御
    三澤 弘明 化学と工業 54 (12) 1377 -1379 2001年 [査読無し][通常論文]
  • フェムト秒超加工による3次元フォトニック結晶の作製
    三澤 弘明 レーザー加工学会誌 8 (3) 7 -10 2001年 [査読無し][通常論文]
  • 集光フェムト秒レーザーによる透明材料のナノ加工
    三澤 弘明 NEW GLASS 16 (3) 38 -41 2001年 [査読無し][通常論文]
  • 三澤 弘明 表面科学 22 (11) 729 -734 2001年 [査読無し][通常論文]
     
    Photomodification of transparent dielectric materials, induced by tightly focused laser beams, can be utilized for the fabrication of 3 D photonic crystal (PhC) structures. The photomodification occurs in the focal region of the beam due to multiphoton absorption. Nonlinearity of this process allows to reduce the size of the photomodified region even below the diffractive limit of the focusing optics. We utilize two types of photomodification for the PhC fabrication: (i) damage in silica glass that leaves empty voxels, and (ii) polymerization in liquid resins that leaves solid voxels. By damaging/solidifying the initial materials at precisely controlled periodic locations, we have recorded 3 D PhC structures. Using the (i) process we have recorded PhCs in silica with 3 D fcc lattice types, which exhibit clear signatures of photonic bandgaps in the near IR spectral region. With (ii) process we have recorded log-pile PhC structures, which exhibit photonic bandgaps and microcavity effects in the same spectral region.
  • 超高感度マイクロ集積化分析システムの開発
    三澤 弘明 STEPねっとわ〜く 2 10 -12 2001年 [査読無し][通常論文]
  • 三澤 弘明 電気学会論文誌E センサマイクロマシン準部門誌 121 (4) 158 -162 2001年 [査読無し][通常論文]
     
    We synthesized a micro lens array with variable focal length by micromachining a gel which expands and contracts in response to pH stimulation. The silicone template was made as a mold for the lens array. Acrylic acid was polymerized on the moid and the polymerized gel was used as the lens array. The micro lens swelled and shrunk in response to pH change. The focal length change was investigated using the same composition of poly(acrylic acid) gel. In the future, we will create a device which can improve image processing efficiency by adjusting the lens focal length only in the region corresponding to the particular image to be sharpened among the images already captured on the light-receiving surface. © 2001, The Institute of Electrical Engineers of Japan. All rights reserved.
  • 多光子吸収による三次元マイクロファブリケーション
    三澤 弘明 化学工業 52 (4) 14 -18 2001年 [査読無し][通常論文]
  • フェムト秒加工
    三澤 弘明 オプトニューズ 1 33 -34 2001年 [査読無し][通常論文]
  • J. Song, H. Sun, Y. Xu, Y. Fu, S. Matsuo, H. Misawa, G. Du Optical and Quantum Electronics 32 (12) 1295 -1300 2000年12月 [査読無し][通常論文]
     
    Three-dimensional polystyrene/air photonic crystal structure with different particle diameters: 200, 270 and 340 nm was achieved. Strong photonic band gap effect reflected with transmission minimum down to -16 dB was observed. The central wavelengths of the valleys of spectra were well fitted with theoretical calculation. The augmentation of band gap effect versus particle diameter was attributed to an improved self-assembling of particles. An analysis of transmission spectra is also presented. The agreement between the results of experiment and numerical analysis is good.
  • Hiroaki Misawa, Saulius Juodkazis, Andrius Marcinkevi?ius, Vygantas Mizeikis, Akira Yamaguchi, Hongbo Sun, Shigeki Matsuo Proceedings of the International Symposium on Micro Machine and Human Science 23 -33 2000年12月01日 [査読無し][通常論文]
     
    We describe microfabrication of various materials by multi-photon absorption (MPA) of femtosecond (120-150 fs) light pulses. The photo-modification at the focal point of tightly focused laser beam occurs inherently within volume smaller than that defined by the diffraction limit. The achievable lateral resolution is compared with that obtainable by lithography which uses near-field optical microscopy (NSOM). This technique can in principle lead to the realization of 3D optical memory and photonic crystals (PhC) with arbitrary lattice in polymers and silica glass, 3D prototyping in polymerizable resins, and etching of 3D structures guided by the optically damaged pattern in silica. Another topic also discussed in this work deals with laser micromanipulation using continuos wave (cw) laser operating at 1.06 μm. Light-controlled revolution of liquid crystal droplet and volume-phase transition of gel will be described.
  • M Watanabe, S Juodkazis, S Matsuo, J Nishii, H Misawa JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 39 (12A) 6763 -6767 2000年12月 [査読無し][通常論文]
     
    We report the readout of three-dimensional (3-D) memory of bits from their photoluminescence (PL). The bits were recorded inside vitreous silica by optical damage (micro-explosion), which was induced by 150 fs single pulse irradiation at the focal point. The bit can be written by 0.2-0.5 muJ energy pulses at 400 nm or 800 nm (the pulse energy was given at the irradiation point and had an intensity of about 10(15) W/cm(2) when a high numerical aperture of NA = 1.3 objective lens was used for recording). The readout was obtained by the PL of the 3-D pattern of damaged bits, which were excited by quasi-continuos (repetition rate of 82 MHz) fs-irradiation at much lower pulse intensity (by a factor of 10(6)) in order to exclude secondary damage. The readout was performed by the oil-immersion objective lens of NA = 1.3. The wavelength of PL excitation was 400 nm for one-photon and 800 nm for two-photon excitation of pi, with the single pulse energy of less than 1 pJ. We found that the crosstalk of pi, readout is the same as that for the transmission imaging and measures 4 mum in the inter-plane distance for the case of one-photon excitation and can be reduced to 3 mum when a reflection-type readout system is used together with two-phr,ton excitation (theoretical axial hit size for fabrication of a given optics was 1.4 mum). Two-photon readout of 3-D memory in silica is demonstrated for the first time.
  • 久保豊和, 高木均, 岡野耕次, 三澤弘明, 松尾繁樹, 浅井真人 計算力学講演会講演論文集 2000 (13) 453 -454 2000年11月27日 [査読無し][通常論文]
  • 三澤 弘明 日本機械学会誌 103 (984) 749 -751 2000年11月05日
  • S Juodkazis, N Mukai, R Wakaki, A Yamaguchi, S Matsuo, H Misawa NATURE 408 (6809) 178 -181 2000年11月 [査読無し][通常論文]
     
    Many polymer gels undergo reversible, discontinuous volume changes in response to changes in the balance between repulsive intermolecular forces that act to expand the polymer network and attractive forces that act to shrink it. Repulsive forces are usually electrostatic or hydrophobic in nature, whereas attraction is mediated by hydrogen bonding or van der Waals interactions. The competition between these counteracting forces, and hence the gel volume(1-3), can thus be controlled by subtle changes in parameters such as pH (ref. 4), temperature(5), solvent composition(6) or gel composition(7). Here we describe a more direct influence on this balance of forces, by showing that the radiation force generated by a focused laser beam induces reversible shrinkage in polymer gels. Control experiments confirm that the laser-induced volume phase transitions are due to radiation forces, rather than local heating, modifying the weak interactions in the gels, in agreement with previous observations of light-induced chain association in polymer solutions(8,9). We rnd that, owing to shear-relaxation processes(10), gel shrinkage occurs up to several tens of micrometres away from the irradiation spot, raising the prospect that the combination of stimuli-responsive polymer gels and laser light might lead to new gel-based systems for applications such as actuating or sensing.
  • 三澤 弘明 光化学 = Photochemistry 31 (2) 139 -141 2000年08月01日
  • T Karatsu, H Itoh, A Nishigaki, K Fukui, A Kitamura, S Matsuo, H Misawa JOURNAL OF PHYSICAL CHEMISTRY A 104 (30) 6993 -7001 2000年08月 [査読無し][通常論文]
     
    The photochemical reactions (Z-E isomerization and photocyclization) of the s-cis and s-trans rotamers of (Z)-1-[2-(1-methryl)-2-phenylethene (Z2APE) were investigated. The absorption, steady-state and picosecond time-resolved fluorescences, and transient absorption spectra were measured in order to achieve a better understanding of the rotamer photochemistry. The spectra were compared with those of the model compounds ((Z)-1-[2-(1 -methylanthryl)]-2-phenylethene: Z1Me2APE and (Z)-1 -[2-(3-methylanthryl)]-2-phenylethene: Z3Me2APE). It is confirmed that the s-trans rotamer undergoes only Z-E adiabatic isomerization and that the s-cis rotamer mainly photocyclizes to give the dihydrophenanthrene-type intermediate with a much faster rate constant (k(cyc) = 2.3 x 10(10) s(-1).) The reason Z2APE does not give an aromatized pholocyclization product (1,2-naphtho[a]anthracene, NA) is that the return of the dihydrophenanthrene-type intermediate to the Z isomer is much faster than the oxidation to produce NA.
  • K Ueno, F Kitagawa, HB Kim, T Tokunaga, S Matsuo, H Misawa, N Kitamura CHEMISTRY LETTERS (8) 858 -859 2000年08月 [査読無し][通常論文]
     
    A polymer microchannel (width = 100 mu m and depth = 20 mu m) chip integrated with band Au electrodes (47 x 100 mu m) was fabricated on the basis of photolithography/etching and imprinting techniques, and its characteristic electrochemical responses have been demonstrated.
  • HB Sun, T Kawakami, Y Xu, JY Ye, S Matuso, H Misawa, M Miwa, R Kaneko OPTICS LETTERS 25 (15) 1110 -1112 2000年08月 [査読無し][通常論文]
     
    Effective energy windows for two-photon absorption (TPA) photopolymerization of resins were investigated and, with a properly selected laser pulse energy, exquisite three-dimensional (3D) microstructures with submicrometer spatial resolution were achieved. The results show the inherent utility of TPA in the fabrication of real 3D patterns. In particular, we propose and utilize a resin pre-exposure technique by which freely movable components affixed to an axle are built, demonstrating a new application of TPA in laser microfabrication. (C) 2000 Optical Society of America OCIS codes: 220.3740, 220.4000, 230.4000, 160.4330, 190.4180, 160.5470.
  • 三澤弘明, 小松真也, 金鵬, 塩田将弘, 松尾繁樹, 大井文香, 上甲茂樹 年次大会講演論文集 : JSME annual meeting 2000 (1) 307 -308 2000年07月31日 [査読無し][通常論文]
     
    We fabricated the gold micro-electrode using the micromachining technology. Glucose oxidase (GOD) was immobilized on the gold micro-electrode by the thiol derivative. We succeeded in the development of the micro sensor which electrochemically detects the glucose using this GOD immobilized gold microelectrode. It was possible to detect 1-30mM glucose using this micro glucose sensor.
  • 岡野耕次, 高木均, 八木哲也, 三澤弘明, 松尾繁樹, 浅井真人 年次大会講演論文集 : JSME annual meeting 2000 (3) 343 -344 2000年07月31日 [査読無し][通常論文]
     
    In recent years, electronic devices are miniaturized, and we wish to develop microactuator. Ni-Ti shape memory alloy is a material adapted to micro actuator as it can keep high power/weight ratio if it's miniaturized. So, a lot of studies have researched on this field. But, the research on the performance of thin films for actuator specifically did not reported frequently. Therefore, in our study, we researched recovery behavior of Ni-Ti shape memory alloy thin films; it is important for its practical application into microactuator to research on recovery force and response behavior.
  • HB Sun, Y Xu, JY Ye, S Matsuo, H Misawa, JF Song, GT Du, SY Liu JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 39 (6B) L591 -L594 2000年06月 [査読無し][通常論文]
     
    Colloidal assemblies consisting of monotonic polystyrene microspheres with a controlled degree of ordering were fabricated, and exhibited rich spectral behaviors. Smooth and spike-modulated broad attenuation regions in transmission spectra were observed in highly disordered and partly disordered samples, respectively, in contrast to the narrow peaks observed in well-ordered photonic crystals. These properties are interpreted consistently by analyzing the variation of the volume of closely packed units.
  • HB Sun, JF Song, Y Xu, S Matsuo, H Misawa, GT Du, SY Liu JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS 17 (3) 476 -480 2000年03月 [査読無し][通常論文]
     
    High-quality three-dimensional polystyrene-air photonic crystal structures with particle diameters of 200, 270, and 340 nm were grown with a quasi-equilibrium evaporation technique. The effects of the removal of interval water were evident as a blueshift of peaks, enhancement of the transmission attenuation, and changes in the gap/midgap ratio. Frequency scaling and incidence-angle-dependent transmission were also investigated; both show good agreement with the numerical simulation. (C) 2000 Optical Society of America [S0740-3224(00)01103-6] OCIS codes: 290.5850, 310.2790, 310.6860, 160.4670, 160.4760, 160.4890.
  • 岡野耕次, 八木哲也, 高木均, 三澤弘明, 松尾繁樹, 浅井真人 講演論文集 5 (1) 73 -74 2000年02月25日 [査読無し][通常論文]
  • S Juodkazis, PG Eliseev, M Watanabe, HB Sun, S Matsuo, T Sugahara, S Sakai, H Misawa JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 39 (2A) 393 -396 2000年02月 [査読無し][通常論文]
     
    We report experimental data on photoluminescence (PL) annealing of metalorganic chemical vapor deposition (MOCVD) grown GaN-InGaN multi quantum wells (MQWs). The formation of phase separation in the InGaN quantum well layer was confirmed by PL mapping when the MQW was grown at 675 degrees C. Spatial distribution of the yellow (Y)-band PL correlated with the dislocation network in that the intensity of the PL was lowest at the grain boundaries. The activation energy of thermal quenching of the InGaN PL at 400 nm was found to be equal to that of the increase of Y-band PL at 550 nm. The origin of the Y-band is explained as a radiative donor-acceptor recombination.
  • S Juodkazis, M Watanabe, HB Sun, S Matsuo, J Nishii, H Misawa APPLIED SURFACE SCIENCE 154 696 -700 2000年02月 [査読無し][通常論文]
     
    We report the observation of photoluminescence (PL) in optically damaged vitreous silica (v-SiO2) and its gradual decrease by annealing at temperature range from room temperature to 773 K. Optical damage was induced by tightly focused picosecond or femtosecond irradiation inside v-SiO2. FL bands at 280, 470 and 650 nm were observed. The PL can be excited by 250 nm irradiation, which corresponds to the absorption band of the oxygen vacancy, V-O. The decrease of PL with annealing is explained by structural modifications of the defects in the damaged area. (C) 2000 Elsevier Science B.V. All rights reserved.
  • K Yamasaki, S Juodkazis, M Watanabe, HB Sun, S Matsuo, H Misawa APPLIED PHYSICS LETTERS 76 (8) 1000 -1002 2000年02月 [査読無し][通常論文]
     
    We report the recording of a three-dimensional (3D) pattern in bulk polymethyl metacrylate (PMMA) films by microexplosion induced by a tightly focused (numerical aperture of oil-immersion objective was 1.3) single laser shot. Recording was done by picosecond (ps) single-pulse irradiation at 532 nm and by femtosecond at a 400 nm wavelength. The light-induced damage threshold of PMMA was found at similar to 4 MW/cm(2) for ps damaging. Readout of the 3D pattern was carried out by the recording of the transmission and the photoluminescence (PL) of bits. We demonstrate the possibility exciting PL of the optically damaged area inside the PMMA by one- and two-photon absorption. (C) 2000 American Institute of Physics. [S0003-6951(00)03208-3].
  • 上野貢生, 北川文彦, 金幸夫, 喜多村のぼる, 三沢弘明 分析化学討論会講演要旨集 61st 2000年
  • 上野貢生, 金幸夫, 三沢弘明, 喜多村昇 化学とマイクロシステム研究会講演要旨集 2nd 2000年
  • Formation of Al203 Based photonic Crystals
    Lithuanian Journal of Physics (40) 155 -159 2000年 [査読無し][通常論文]
  • Appl. Phys. Lett. 77 (1) 13 -15 2000年 [査読無し][通常論文]
  • Photoluminescence Imaging. The Issues of Vibration Noise in Near-Field Optical Microscopy
    Lithuanian Journal of Physics (40) 237 -241 2000年 [査読無し][通常論文]
  • Surface Morphology of GaN Layers
    Lithuanian Journal of Physics (40) 113 -117 2000年 [査読無し][通常論文]
  • Trapping of Microstructures by Laser Scanning Manipulation(共著)
    T. IEE Japan, (120) 345 -349 2000年 [査読無し][通常論文]
  • T. SICE, (36) 459 -461 2000年 [査読無し][通常論文]
  • Jpn. J. Appl. Phys., (39) 1930 -1933 2000年 [査読無し][通常論文]
  • J. Phys. Chem. B, (104) 3450 -3455 2000年 [査読無し][通常論文]
  • 光応用:レーザトラップ
    三澤 弘明 日本機械学会 103 (948) 90 -92 2000年 [査読無し][通常論文]
  • マイクロ三次元光造形
    三澤 弘明 レーザ熱加工研究会誌 7 (2) 26 -30 2000年 [査読無し][通常論文]
  • M Watanabe, S Juodkazis, HB Sun, S Matsuo, H Misawa PHYSICAL REVIEW B 60 (14) 9959 -9964 1999年10月 [査読無し][通常論文]
     
    We report the observation of photoluminescence (PL) originating from defects created by the visible and near-infrared irradiation of vitreous silica. Three PL bands at 283, 468, and 558 nm exhibited excitation spectra peaking at 250 nm, which corresponds to the oxygen vacancy defect V-o absorption. The observed PL bands can be attributed to the following transitions: the singlet-singlet transition of oxygen vacancy for 283 nm, and the radiative recombination of separated carriers on the vacancy-interstitial pairs (V-o ;O-i) and(V-o ;(O-2)(i)) for 468 and 558 nm, respectively. [S0163-1829(99)07337-3].
  • S Juodkazis, H Ishii, S Matsuo, H Misawa JOURNAL OF ELECTROANALYTICAL CHEMISTRY 473 (1-2) 235 -239 1999年09月 [査読無し][通常論文]
     
    Submicrometer patterning of the TiO2-rutile single crystal surface by Pt was accomplished by means of photo-catalytic reduction of PtCl42- from aqueous solutions of H2PtCl6. The patterns of Pt were fabricated along focal point traces of a 380 nm wavelength excitation laser beam. Single particles of Pt as small as 100 nm can be grown by such techniques. (C) 1999 Elsevier Science S.A. All rights reserved.
  • PG Eliseev, HB Sun, S Juodkazis, T Sugahara, S Sakai, H Misawa JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 38 (7B) L839 -L841 1999年07月 [査読無し][通常論文]
     
    The laser-induced damage of epitaxially grown GaN semiconductor material is investigated for the first time by illumination of the c-plane by sub-picosecond laser pulses at the wavelength of 400 nm. The surface damage was investigated by optical and atomic force microscopies. The threshold fluence for ablation damage is determined to be similar to 5.4 J/cm(2) for pulse width of 150 fs. An application is demonstrated for laser-beam processing by the formation of clean dips on the GaN surface to depths of 240 nm in a single shot.
  • S Juodkazis, M Shikata, T Takahashi, S Matsuo, H Misawa APPLIED PHYSICS LETTERS 74 (24) 3627 -3629 1999年06月 [査読無し][通常論文]
     
    We demonstrate the feasibility of an all-optical liquid-crystal (LC) switch with submillisecond switching time. This switch is realized by optical manipulation of a three-dimensionally trapped microscopic nematic LC droplet using an "optical tweezers." Transmission of a polarizer/LC droplet/analyzer system can be modulated at frequencies as high as 10(3) Hz, a faster response than that of a nematic LC demonstrated so far. The response corresponds to a submillisecond switching time when the LC droplet is rotated by an angle of pi/4. The alignment of the LC droplet to the plane of the incident plane-polarized beam is also demonstrated. (c) 1999 American Institute of Physics. [S0003-6951(99)00124-2].
  • H Misawa, S Juodkazis PROGRESS IN POLYMER SCIENCE 24 (5) 665 -697 1999年06月 [査読無し][通常論文]
     
    In this article we survey experimental results obtained by the employment of the technique called "scanning laser micromanipultion". Novel physical and chemical properties of material of micro- and sub-micrometer dimensions are elucidated by conducting experiments on an individual laser-tweezed particle. It is shown that scanning laser micromanipulation can be adopted to the particles which have a refractive index that is higher than that of the surrounding material, as well as to those which possess lower refractive index or are reflective. An implementation of this method of laser manipulation can be applied for micro-machining, optical switching and electrochemistry, as demonstrated by a series of examples. (C) 1999 Elsevier Science Ltd. All rights reserved.
  • S Juodkazis, M Shikata, T Takahashi, S Matsuo, H Misawa JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 38 (5A) L518 -L520 1999年05月 [査読無し][通常論文]
     
    We report the development of an all-optical liquid-crystal (LC) switch realized by laser manipulation of a three-dimensionally trapped micrometer-size nematic liquid-crystal droplet. Transmission of a polarizer/LC droplet/analyzer system can be modulated at a frequency as high as 10(3) Hz for micrometer sized LC droplets. An optical switching corresponds to the rotation of the LC droplet by an angle of pi/4. The dependence of rotation frequency on LC droplet size is explained in terms of the circularly polarized light scattering by the molecules of the LC droplet. This scattering is responsible for the transfer of angular momentum from the light to the LC droplet.
  • M Horiyama, HB Sun, M Miwa, S Matsuo, H Misawa JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 38 (2B) L212 -L215 1999年02月 [査読無し][通常論文]
     
    Three-dimensional microstructures with aspect ratios larger than 20 and a solidified wall with a thickness down to 2.0 mu m have been fabricated by the one-photon absorption photopolymerization technique. Lateral and longitudinal spatial resolutions in a single-line scanning process of as high as 1.0 mu m and 0.3 mu m, respectively, are reproducible. An experimental system consisting of a common picosecond pulsed laser and an optical microscope makes laser microfabrication easy to realize, implying a broad application potential.
  • HB Sun, S Matsuo, H Misawa APPLIED PHYSICS LETTERS 74 (6) 786 -788 1999年02月 [査読無し][通常論文]
     
    Three-dimensional photonic crystal structures were fabricated with laser microfabrication techniques through two-photon-absorption photopolymerization of resin. Significant band-gap effects in the infrared wavelength region were observed from "layer-by-layer'' structures. (C) 1999 American Institute of Physics. [S0003-6951(99)03506-8].
  • 上野貢生, 金幸夫, 喜多村のぼる, 三沢弘明 分析化学討論会講演要旨集 60th 1999年
  • 上野貢生, 武内伸代, 金幸夫, 喜多村のぼる, 三沢弘明 日本分析化学会年会講演要旨集 48th 1999年
  • 喜多村昇, 上野貢生, 三沢弘明, KIM H-B 日本化学会講演予稿集 76th (1) 1999年
  • 喜多村昇, 千葉真弘, 上野貢生, 三沢弘明, KIM H-B 日本化学会講演予稿集 76th (1) 1999年
  • Spectral Shift in Lasing Wavelengths due to Optical Kerr Effect in a Dye-doped Microsphere of Organic Polymer(共著)
    Nonlinear Optics, (22) 397 -400 1999年 [査読無し][通常論文]
  • Transmission and Photoluminescence Images of Three-Dimensional Memory in Vitreous SiLica(共著)
    Applied Physics Letters 74 (6) 786 -788 1999年 [査読無し][通常論文]
  • Progress in Polymer Science 24 (5) 665 -697 1999年 [査読無し][通常論文]
  • Microfabrication and Characteristics of Two-Dimensional Photonic Crystal Structures in Vitreous Silica(共著)
    Opt. Rev. 6 112 -114 1999年 [査読無し][通常論文]
  • Suzuki, I, R Tanaka, A Yamaguchi, S Maki, H Misawa, K Tokumaru, R Nakagaki, H Sakuragi BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 72 (1) 103 -113 1999年01月 [査読無し][通常論文]
     
    The reaction course of acyl-diphenylmethyl biradicals (alpha-oxo-omega, omega-diphenyl-alpha, omega-alkanediyl biradicals), O=C-up arrow-(CH2)(n-2)-(CPh2)-Ph-up arrow ((BR)-B-3-n), generated from the Norrish type-I reaction of 2,2-diphenylcycloalkanones (CK-n) with various ring sizes in methanol, is switched from intramolecular disproportionation (n = 6, 7), giving a diphenylalkenal, to acylphenyl recombination (n greater than or equal to 9), affording a cyclophane derivative. The behavior of (BR)-B-3-9 derived from CK-9 was studied in detail; the photolysis of CK-9 afforded an open-chain and a cyclic decarbonylation product together with an unsaturated aldehyde and a 4-methylene-2,5-cyclohexadienyl ketone (a pre-cyclophane). The photolysis of this ketone gave the same products that arose from the photolysis of CK-9, presenting the possibility that the decarbonylation products and a part of the aldehyde are formed as secondary products during irradiation. The magnetic field dependence of the lifetimes of (BR)-B-3-n (n = 12 and 13) generated from CK-12 and 13, respectively, was measured in methanol by means of a pulsed-laser excitation technique. The rate constants for intersystem crossing showed a maximum at a relatively low field strength, which decreased with increasing the field strength to level off to an asymptotic value at > 1.5 kG. The results show that the role of hyperfine coupling in intersystem crossing is less important in these systems, presumably because of the presence of a carbonyl oxygen and the absence of a hydrogen atom at the radical center.
  • T Takahashi, K Fujiwara, S Matsuo, H Misawa JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 120 (2) 135 -140 1999年01月 [査読無し][通常論文]
     
    Energy transfer from excited state donor to ground state acceptor dyes in polymer microparticles with a diameter of 30-60 mu m was observed under lasing condition. The energy transfer efficiency was found to be higher with the increasing size of the particle. This result indicates that the excitation energy transfer efficiency can be controlled by the particle size without varying temperature and dye concentration. The dynamics of energy transfer was observed through picosecond time-resolved emission spectral measurements. (C) 1999 Elsevier Science S.A. All rights reserved.
  • 三澤 弘明 レーザー研究 27 (12) 817 -822 1999年 [査読無し][通常論文]
  • 三澤 弘明 O plus E 21 (12) 1549 -1553 1999年 [査読無し][通常論文]
  • 自己積層高分子薄膜を用いたマイクロ血球分離システムの開発
    大井文香, 青木秀憲, 太田聡, 上甲茂樹, 松尾繁樹, 三澤弘明 電子情報通信学会論文誌 3 99 (178) 67 -73 1999年 [査読無し][通常論文]
  • 多光子吸収による三次元マイクロファブリケーション
    三澤 弘明 SUT Bulletin 16 (8) 8 -13 1999年 [査読無し][通常論文]
  • 川上剛史, 松尾繁樹, 三澤弘明, 三輪昌史, 金子礼三 レーザー学会研究会報告 = Reports on the Topical meeting of the Laser Society of Japan 259 41 -45 1998年12月14日 [査読無し][通常論文]
  • M Watanabe, HB Sun, S Juodkazis, T Takahashi, S Matsuo, Y Suzuki, J Nishii, H Misawa JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 37 (12B) L1527 -L1530 1998年12月 [査読無し][通常論文]
     
    To achieve high bit densities (>10 GB/cm(3)) in optical memory, we accomplished a three-dimensional optical data storage system using vitreous silica as the recording material. We succeeded in high-density optical recording by focusing pulsed laser beams of 532 nm (full width at half maximum [FWHM] 30 ps) and 400 nm (150 fs). A recording density of 72.9 GB/cm(3) was achieved, which corresponded to that of 100 compact disks, on a glass plate of (2 x 2) cm(2) and 2.2 mm thickness. We found that the optical damage of silica occurs within 400 ps after irradiation by a single pulse for 30 ps at 532 nm. Three photoluminescence bands were found in the photomodified silica at 283 nm, 468 nm and 558 nm. All the three bands showed similar photoluminescence excitation spectra, i.e. a peak related to oxygen vacancy absorption at 250 nm.
  • T Takahashi, S Matsuo, H Misawa, T Karatsu, A Kitamura, K Kamada, K Ohta THIN SOLID FILMS 331 (1-2) 298 -302 1998年10月 [査読無し][通常論文]
     
    Laser oscillation from dye-doped microparticles of organic polymers was investigated. Spectral shift in peak wavelengths of laser oscillation depending on pumping intensity was observed in the microparticles of poly(cyclohexylmethylsilane) (PCHMSi). The shift observed for PCHMSi microparticles was discussed in terms of the third-order non-linear optical (NLO) effect. It was concluded that the effective power density of light just inside the microparticle's surface was about 30 times larger than that of the pump pulse. (C) 1998 Elsevier Science S,A, All rights reserved.
  • 朴 鐘震, 入江 正浩, 増原 宏, 橋本 和仁, 三澤 弘明 光化学 = Photochemistry 28 (1) 2 -16 1998年08月25日
  • H Ishii, S Juodkazis, S Matsuo, H Misawa CHEMISTRY LETTERS (7) 655 -656 1998年07月 [査読無し][通常論文]
     
    Submicrometer patterning of TiO2-rutile single crystal surface by Pt was accomplished by means of photocatalytic reduction of PtCl42- to Pt in an aqueous solution of H2PtCl6. The patterns of Pt were fabricated along focal point traces of 380 nm wavelength excitation laser beam on the surface of rutile substrates.
  • K Fukuda, H Sun, S Matsuo, H Misawa JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 37 (5A) L508 -L511 1998年05月 [査読無し][通常論文]
     
    We demonstrated that low-velocity quasi-equilibrium evaporation of water from an aqueous colloidal solution of polystyrene microparticles with 220 nm diameter enabled the preparation of a three-dimensional colloidal-air photonic crystal structure without significantly distorting the lattice, and the absorption peak of the structure was observed at around 500 nm. A much stronger photonic band gap effect is expected due to an approximately 30% increase of the dielectric contrast.
  • 多光子吸収によるガラス光メモリー
    三澤 弘明 O plus E 20 (9) 1028 -1032 1998年 [査読無し][通常論文]
  • 多光子吸収励起過程を利用した三次元光記録
    三澤 弘明 光技術コンタクト 36 (3) 124 -129 1998年 [査読無し][通常論文]
  • マイクロマシン技術とその応用
    三澤 弘明 STEP テクノ情報 3 (4) 2 -6 1997年 [査読無し][通常論文]
  • 三澤 弘明, 三輪 昌史 精密工学会誌 63 (7) 959 -962 1997年 [査読無し][通常論文]
  • マルチフォトンプロセスを用いた三次元記録
    三澤 弘明 光化学 24 26 -31 1997年 [査読無し][通常論文]
  • 三澤 弘明 レーザー研究 24 (11) 1163 -1168 1996年11月25日
  • 三澤 弘明 化学と工業 = Chemistry and chemical industry 49 (2) 178 -180 1996年02月01日
  • 三澤 弘明 レーザー研究 24 (7) 750 -756 1996年 [査読無し][通常論文]
     
    Laser manipulation-microfabrication system consisting of a CW laser, a picosecond pulsed laser and an optical microscope was developed to assemble micrometer-sized structure in solution. Photopolymerization of reactive monomers induced at the focal spot of picosecond laser pulses (λ = 355 nm or 532 nm, FWHM = 30 ps, repetation rate = 10 Hz) was employed for connection of glass particles regularly aligned by laser trapping. Since photopolymerization was induced in the vicinity of a focal spot, any desired numbers of glass particles with arbitrary geometrical structure can be connected by repeating the manipulation and the photopolymerization procedures.
  • T Araki, H Misawa REVIEW OF SCIENTIFIC INSTRUMENTS 66 (12) 5469 -5472 1995年12月 [査読無し][通常論文]
     
    A compact pulsed-light source is devised from an InGaN/AlGaN double heterostructure light-emitting diode (LED). The LED emits a 450-nm (blue) light under conventional de operation below 30 mA. When a current larger than 50 mA is applied, the intensity of the 450-nm Light saturates, but that of the 380-nm light due to the InGaN component continues to increase. This phenomenon is utilized to realize a nanosecond ultraviolet (UV) light source. Under repetitive, large current pulsing (frequency=10 kHz, pulse width=4 ns, peak current=2 A), the peak LED emission shifts from 450 to 380 nm. Intense light pulses (peak value=40 mW) of 4-ns duration were generated. To evaluate the potential of the pulsed LED as an excitation source, the fluorescence lifetime of a quinine-sulfate solution was measured. The observed Lifetime characteristics agreed well with the generally accepted behavior. (C) 1995 American Institute of Physics.
  • M Ishikawa, H Misawa, N Kitamura, M Irie, H Masuhara BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 68 (12) 3397 -3402 1995年12月 [査読無し][通常論文]
     
    Photostimulated volume expansion of polyacrylamide microgels (initial radius=11-235 mu m) bearing triphenylmethyl cyanide moieties (AAm-TPMCN) in water was studied on the basis of simultaneous measurements of the degree of ionic dissociation (alpha) of TPMCN to TPM(+) (triphenylmethyl cation) and the gel radius. The time profile of the radius change, r(t), was analyzed by a convolution relation between r(t) and the time course of alpha (alpha(t)). The characteristic time constants of the volume change, related to the cooperative diffusion coefficient of the gel network, were determined for AAm-TPMCN gels with various radii. The faster photoresponse time of the volume change for the smaller AAm-TPMCN gel was explained in terms of the diffusion theory of gel networks in water.
  • M TAJIMA, H MISAWA, H INOUE JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 89 (1) 53 -59 1995年06月 [査読無し][通常論文]
     
    The photochromic behaviour of 1-(2-naphthoxy)anthraquinone (1) was investigated using electronic spectroscopy and kinetic analysis of the decay of coloured species. The decay of coloured species well obeyed first-order kinetics and consisted of two processes, reversion to the starting substance and the change toward final formation of 1-hydroxyanthraquinone (2). The reversion process was revealed to proceed through two different pathways having activation enthalpies of 30.5 and 104 kJ mol-1. The lower value suggests that the reversion proceeds from a rotational isomer of 1 while the higher value comes from a structural isomer of 1, 9-naphthoxy-1,10-anthraquinone. The activation enthalpy of the change toward final formation of 2 was 49.1 kJ mol(-1). The possible formation of the two different coloured species from the two conformers of 1 on light irradiation was discussed.
  • A Biological-sensor Utilizing a Living Cell for Environment Monitoring in Micro Space (共著)
    Proceedings of the International Symposium on Microsystems, Intelligent Materials and Robots 301 1995年 [査読無し][通常論文]
  • Laser Manipulation Technique and Its Role in Study of Micromachine (共著)
    Proceedings of the International Symposium on Microsystems, Intelligent Materials and Robots 67 1995年 [査読無し][通常論文]
  • Sejji Funakura, Kiyoharu Nakatani, Hiroaki Misawa, Noboru Kitamura, Hiroshi Masuhara Journal of Physical Chemistry 99 (41) 15192 -15197 1995年 [査読無し][通常論文]
     
    Transient absorption microspectroscopy was developed for studies on photophysical and photochemical processes in a single laser-manipulated microdroplet in water. Transient absorption spectra and their decay curves of individual tri-n-butyl phosphate (TBP) microdroplets containing zinc tetraphenylporphyrin (ZnTPP) were measured and analyzed. Owing to the intense laser excitation, the concentration of the ZnTPP triplet state was so high that the decay profiles of Tn ← T1 absorbance of ZnTPP obeyed the second-order kinetics, triplet-triplet (T-T) annihilation. Simultaneously the delayed fluorescence of ZnTPP was observed and analyzed in terms of T-T annihilation. The estimated rate constant of T-T annihilation (kTT) was comparable to that obtained from Tn ← T1 absorption spectroscopy. Assuming the T-T annihilation is diffusion-controlled, the inner viscosity of a single TBP microdroplet was obtained and examined as a function of the diameter of the microdroplets. A remarkable micrometer size effect that the inner viscosity is decreased with the droplet diameter was found and discussed in terms of a swollen TBP droplet owing to the penetration of water. © 1995 American Chemical Society.
  • 光の「圧力」による微粒子操作法
    三澤 弘明 メカライフ 44 32 -33 1995年 [査読無し][通常論文]
  • 三澤 弘明 應用物理 63 (9) 898 -905 1994年09月10日
  • Kiyoharu Nakatani, Tatsuya Uchida, Hiroaki Misawa, Noboru Kitamura, Hiroshi Masuhara Journal of Electroanalytical Chemistry 367 (1-2) 109 -114 1994年03月04日 [査読無し][通常論文]
     
    The electrochemistry of ferrocene (FeCp) in a single micrometer-sized nitrobenzene droplet dispersed in water was studied by laser trapping and microelectrochemical techniques. Mass transfer of FeCp, ferrocenium ion, and tetra-n-butylammonium ion between the droplet and water phases accompanied by oxidation of FeCp proceeded across the droplet | water interface. The peak potential of a cyclic voltammogram of FeCp was highly dependent on the potential sweep rate. The potential shift was analyzed by thin-layer electrolysis and the results are discussed in terms of the irreversible electron transfer of FeCp across the droplet | electrode interface and in terms of mass transfer of ion species across the droplet | water interface. © 1994.
  • Kiyoharu Nakatani, Tatsuya Uchida, Hiroaki Misawa, Noboru Kitamura, Hiroshi Masuhara Journal of Electroanalytical Chemistry 367 (1-2) 109 -114 1994年03月04日 [査読無し][通常論文]
     
    The electrochemistry of ferrocene (FeCp) in a single micrometer-sized nitrobenzene droplet dispersed in water was studied by laser trapping and microelectrochemical techniques. Mass transfer of FeCp, ferrocenium ion, and tetra-n-butylammonium ion between the droplet and water phases accompanied by oxidation of FeCp proceeded across the droplet | water interface. The peak potential of a cyclic voltammogram of FeCp was highly dependent on the potential sweep rate. The potential shift was analyzed by thin-layer electrolysis and the results are discussed in terms of the irreversible electron transfer of FeCp across the droplet | electrode interface and in terms of mass transfer of ion species across the droplet | water interface. © 1994.
  • Seiji Funakura, Kiyoharu Nakatani, Hiroaki Misawa, Noboru Kitamura, Hiroshi Masuhara Journal of Physical Chemistry 98 (12) 3073 -3075 1994年 [査読無し][通常論文]
     
    An absorption microspectroscopy system was developed for absorption measurements of a laser-manipulated individual microdroplet in water under an optical microscope. Absorption spectra of various sizes of individual tri-n-butyl phosphate (TBP) microdroplets containing zinc tetraphenylporphyrin (ZnTPP) were studied as a model. Absorbance of ZnTPP in the droplet was confirmed to increase linearly with the diameter of the droplet, showing that the Lambert-Beer law is followed for droplets with a diameter larger than 6 μm. The concentration of ZnTPP in the droplet dispersed in water is lower than that for pure TBP film by a fixed proportion, which was considered in terms of a constant water partition into TBP. © 1994 American Chemical Society.
  • T KARATSU, H MISAWA, M NOJIRI, N NAKAHIGASHI, S WATANABE, A KITAMURA, T ARAI, H SAKURAGI, K TOKUMARU JOURNAL OF PHYSICAL CHEMISTRY 98 (2) 508 -512 1994年01月 [査読無し][通常論文]
     
    Deuterated ethenylanthracenes, 1-, 2-, and 9-(ethenyl-(Z)-2-d)anthracene, and 2-(ethenyl-(E)-2-d)anthracene ((Z)-1-, 2-, and 9-EAD, and (E)-2-EAD, respectively) undergo photochemical Z-E isomerization under thermal activation. The temperature dependence of their isomerization quantum yields and the temperature independence of lifetimes of their T-n <-- T-1 absorptions indicate that EADs isomerize adiabatically between the Z and E isomers in the lowest excited triplet state by overcoming an activation barrier (E(a) = 19-46 kJ mol(-1)) of the perpendicularly twisted geometry. The activation parameters of isomerization, Delta H double dagger (17-42 kJ mol(-1)) and Delta S double dagger (-40 to -113 J K-1 mol(-1)), decrease in the order of 2-, 1-, and 9-isomers; however, Delta G double dagger (50-54 kJ mol(-1)) is almost constant irrespective of the substitution position of the anthracene nucleus.
  • K SASAKI, H MISAWA, N KITAMURA, R FUJISAWA, H MASUHARA JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS 32 (8B) L1144 -L1147 1993年08月 [査読無し][通常論文]
     
    Optical manipulation of a lasing microparticle in water was demonstrated. A rhodamine B-doped poly(methyl methacrylate) particle was simultaneously manipulated and pumped by 1064 nm CW and 532 nm pulsed Nd3+:YAG laser beams, respectively. Optical interactions between lasing and closely positioned nonlasing particles were studied by a multibeam laser micromanipulation technique.
  • H MISAWA, R FUJISAWA, K SASAKI, N KITAMURA, H MASUHARA JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS 32 (6A) L788 -L790 1993年06月 [査読無し][通常論文]
     
    Simultaneous optical manipulation and lasing of a rhodamine 640-doped polystyrene latex particle in water was demonstrated through irradiation of a single focused 1064 nm CW Nd:YAG laser beam. Lasing of the particle resulting from two-photon absorption was confirmed from periodically spaced peaks in the emission spectrum and from nonlinear (more than quadratic) dependence of the emission intensity upon the incident laser power.
  • K NAKATANI, T UCHIDA, S FUNAKURA, A SEKIGUCHI, H MISAWA, N KITAMURA, H MASUHARA CHEMISTRY LETTERS 4,717 (4) 717 -720 1993年04月 [査読無し][通常論文]
     
    A dye formation reaction between 4-N,N-diethyl-2-methylquinonediimine and a phenol derivative at the oil-droplet/water interface was studied by a microelectrochemical method combined with laser trapping of an individual droplet in an oil-in-water emulsion system. The reaction in a single droplet with almost-equal-to 10 mum diameter was shown to be controlled by the distance between the droplet and a microelectrode.
  • M ISHIKAWA, H MISAWA, N KITAMURA, H MASUHARA CHEMISTRY LETTERS 3,481 (3) 481 -484 1993年03月 [査読無し][通常論文]
     
    Irradiation of a focused 1064 nm laser beam to an aqueous poly(N-isopropylacrylamide) solution resulted in the reversible microparticle (diameter almost-equal-to 7 mum) formation through local heating of water by the laser beam and subsequent phase transition of the polymer solution. The microparticle produced was simultaneously manipulated in three-dimensional space by the incident 1064 nm laser beam.
  • Chemical Physics Letter 210 (1/3) 89 -93 1993年 [査読無し][通常論文]
  • Journal of Physical Chemistry 97 (8) 1701 -1706 1993年 [査読無し][通常論文]
  • H MISAWA, K SASAKI, M KOSHIOKA, N KITAMURA, H MASUHARA MACROMOLECULES 26 (2) 282 -286 1993年01月 [査読無し][通常論文]
     
    Three-dimensional laser manipulation of polymer latex particles in solution was demonstrated. Polymer latex particles with a diameter of several microns were spatially aligned in arbitrary patterns (letters and geometrical figures) by repetitively scanning a focused laser beam (1064 nm) under an optical microscope. Irradiation of nanosecond or picosecond 355-nm laser pulses on individual laser-trapped polymer particles in a sample solution containing polymerizable vinyl monomers and a photoinitiator brought about permanent fixation of the particles in three-dimensional structures. Possible roles of the laser trapping/manipulation techniques in studying the chemistry and physics of polymeric microparticles are also discussed.
  • レーザーによる微粒子のマイクロプロセシング
    三澤 弘明 ケミカルエンジニヤリング 38 (8) 657 -662 1993年 [査読無し][通常論文]
  • レーザー光によるアクチュエーション
    三澤 弘明 M&E(工業調査会) (7) 102 -110 1993年 [査読無し][通常論文]
  • 三澤 弘明, 増原 宏 レーザー研究 21 (1) 146 -148 1993年 [査読無し][通常論文]
  • N KITAMURA, M ISHIKAWA, N TAMAI, H MISAWA, H MASUHARA ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 203 350 -POLY 1992年04月 [査読無し][通常論文]
  • H MASUHARA, N KITAMURA, H MISAWA, K SASAKI, M KOSHIOKA ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 203 599 -POLY 1992年04月 [査読無し][通常論文]
  • H MISAWA, K SASAKI, M KOSHIOKA, N KITAMURA, H MASUHARA ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 203 362 -POLY 1992年04月 [査読無し][通常論文]
  • M KOSHIOKA, H MISAWA, K SASAKI, N KITAMURA, H MASUHARA JOURNAL OF PHYSICAL CHEMISTRY 96 (7) 2909 -2914 1992年04月 [査読無し][通常論文]
     
    Fluorescence characteristics of a single microcapsule containing a toluene solution of pyrene were studied by three-dimensional space- and time-resolved fluorescence spectroscopy. Although pyrene excimer formation dynamics observed for the microcapsules by spatially-unresolved spectroscopy did not obey simple excimer formation kinetics (i.e., Birks kinetic model), that for a single microcapsule measured by spatially-resolved spectroscopy was shown to be described by the Birks kinetics model. The efficiency and dynamics of the excimer formation in individual capsules were different between the capsules owing to the concentration distribution of pyrene in the capsules. The importance of dynamic fluorescence spectroscopy for an individual small particle is discussed.
  • K SASAKI, M KOSHIOKA, H MISAWA, N KITAMURA, H MASUHARA APPLIED PHYSICS LETTERS 60 (7) 807 -809 1992年02月 [査読無し][通常論文]
     
    Laser trapping of a metal particle in water or a water droplet in liquid paraffin, which cannot be attained by irradiation of a TEM00 mode focused laser beam, was experimentally confirmed based on a scanning laser trapping technique. Although a metal particle or a water droplet experiences repulsive radiation force from a laser beam (1064 nm, focused into a approximately 1-mu-m spot), scanning of the laser beam circularly around the particle was successful to optically trap and tweezer the particle. Water and ethylene glycol droplets dispersed in liquid paraffin were also shown to be manipulated independently by scanning double laser-beam trapping.
  • M ISHIKAWA, H MISAWA, N KITAMURA, M IRIE, H MASUHARA CHEMISTRY LETTERS 2,311 (2) 311 -314 1992年02月 [査読無し][通常論文]
     
    The dynamics of photostimulated volume expansion of a polyacrylamide microgel containing triphenylmethane leucocyanide (TPMCN) in water was studied by simultaneous measurements of the time response of absorbance of triphenylmethyl cation (Abs(t)) and the radius of the gel (R(t)). The time response of the degree of ionic dissociation of TPMCN (alpha(t)) in the gel was obtained by analyzing Abs(t) and R(t) for the first time. The change in R(t) was shown to be slower than that in alpha(t).
  • Journal of the American Chemical Society 114 (11) 4417 -4418 1992年 [査読無し][通常論文]
  • H MISAWA, K SASAKI, M KOSHIOKA, N KITAMURA, H MASUHARA APPLIED PHYSICS LETTERS 60 (3) 310 -312 1992年01月 [査読無し][通常論文]
     
    A multibeam laser trapping-reaction system was developed to demonstrate independent manipulation of plural microparticles as well as to induce photochemical reaction in a laser-trapped particle(s). Photopolymerization of vinyl monomers dissolved in a sample solution was employed to fix polystyrene latex particles regularly aligned by laser trapping. Integrated latex structures created by the successive manipulation/polymerization procedures were also shown to be freely manipulated by laser beams.
  • 三澤 弘明 高分子 41 (9) 658 -658 1992年 [査読無し][通常論文]
  • 微粒子のレーザー捕捉・配列法と動的光計測
    笹木 敬司, 三澤 弘明 光技術コンタクト 30 (7) 363 -370 1992年 [査読無し][通常論文]
  • レーザー走査マイクロマニピュレ—ション
    三澤 弘明, 笹木 敬司 光学 21 (2) 91 -92 1992年 [査読無し][通常論文]
  • H MISAWA, M KOSHIOKA, K SASAKI, N KITAMURA, H MASUHARA JOURNAL OF APPLIED PHYSICS 70 (7) 3829 -3836 1991年10月 [査読無し][通常論文]
     
    We developed a laser trapping-ablation system comprised of CW and pulsed Nd3+:YAG lasers as well as of an optical microscope. Three-dimensional manipulation of various kinds of particles and laser ablation of a single optically trapped, poly(methyl methacrylate) latex particle in water were demonstrated. A minute hole with its diameter of approximately sub-mu-m was fabricated on the latex particle (approximately 6-mu-m diameter). The hole size produced was much smaller than the effective diameter of the excitation laser beam, suggesting nonlinear optical (self-focusing of the laser beam) and photochemical (multiphoton absorption) mechanisms for the present laser trapping ablation. Characteristic features of the laser trapping-ablation are discussed in detail.
  • H MISAWA, M KOSHIOKA, K SASAKI, N KITAMURA, H MASUHARA CHEMISTRY LETTERS 3,469 (3) 469 -472 1991年03月 [査読無し][通常論文]
     
    Polystyrene latex particles with the diameter of almost-equal-to 1-mu-m in water were laser trapped in spatial images of a laser beam. For a mixture of latex particles with different diameters, delicate tuning of the images resulted in size selection of the particles. Directional flow of the particles in water was also achieved by laser irradiation.
  • Journal of the American Chemical Society 113 (21) 7859 -7863 1991年 [査読無し][通常論文]
  • Keiji Sasaki, Masanori Koshioka, Hiroaki Misawa, Noboru Kitamura, Hiroshi Masuhara Japanese Journal of Applied Physics 30 (5) 907 -909 1991年 [査読無し][通常論文]
     
    Laser-scanning micromanipulation and spatial patterning of polystyrene latex or titanium dioxide particles in solution were demonstrated for the first time. A trapping laser beam was repetitionary scanned at 13-50 Hz by computer-con­trolled galvano mirrors to align micrometer-order particles along the pattern produced by the scanning laser beam. Char­acteristic features of the present technique are discussed. © 1991 The Japan Society of Applied Physics.
  • 三澤 弘明, 増原 宏 レーザー研究 19 (5) 433 -439 1991年 [査読無し][通常論文]
  • レーザーマニピュレ—ションによる単一微粒子の化学
    三澤 弘明, 増原 宏 光アライアンス 2 (6) 23 -26 1991年 [査読無し][通常論文]
  • H MISAWA, M KOSHIOKA, K SASAKI, N KITAMURA, H MASUHARA CHEMISTRY LETTERS 8,1479 (8) 1479 -1482 1990年08月 [査読無し][通常論文]
  • 水中における単一高分子微粒子のレーザー捕捉・分光・アブレーション
    8,1479 1990年 [査読無し][通常論文]

受賞

  • 2016年08月 The 4th International Symposium on Rare Earth Resource (ISRERU-4) and the 7th International Symposium on Functional Materials (ISFM-7) Functional Materials Scientist Award
     Plasmon-induced photoenergy conversion systems 
    受賞者: 三澤 弘明
  • 2016年08月 Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Honorable Speaker for the Applied Chemistry Lecture Series
     Plasmon-induced photoenergy conversion systems 
    受賞者: 三澤 弘明
  • 2016年03月 日本化学会 2015年度日本化学会賞
     金属ナノ構造を用いた光反応場の創成とその光エネルギー変換への展開 
    受賞者: 三澤 弘明
  • 2015年04月 文部科学省 平成27年度 科学技術分野の文部科学大臣表彰(研究部門)
     プラズモニック化学とその人工光合成への展開に関する研究 
    受賞者: 三澤 弘明
  • 2013年09月 光化学協会 2013年度光化学討論会特別講演賞
     
    受賞者: 三澤 弘明
  • 2006年 公益社団法人日本化学会 2006年度日本化学会学術賞
     超高密度フォトン束による固体の光反応制御 
    受賞者: 三澤 弘明
  • 2005年 光化学協会 2005年度光化学協会賞
     超高強度レーザー光による固体の光反応制御 
    受賞者: 三澤 弘明
  • 1992年 モエヘネシー・ルイビトン 国際科学賞「芸術のための科学」における 「ダビンチ優秀賞」
     
    受賞者: 三澤 弘明

共同研究・競争的資金等の研究課題

  • 日本学術振興会:科学研究費助成事業 特別推進研究
    研究期間 : 2018年04月 -2023年03月 
    代表者 : 三澤 弘明, 笹木 敬司, 上野 貢生, Biju V・Pillai, 村越 敬
     
    電磁場シミュレーションにより、本モード強結合とアンサンブル強結合との差異に関する理解を深めた。その中で、金ナノディスクの密度が比較的低い状態においては、結合強度がアンサンブル強結合と同様ディスク数の1/2乗に比例して増強されることを確認したが、数密度が増大して金ナノディスク間距離が近接すると近接場相互作用により、結合強度がアンサンブル強結合に比べて増強することを明らかにし、実験的にもそれを確認した。 また、金ナノディスクの数密度が低い状態において吸収スペクトル、および近接場スペクトルが飽和する現象を解明するため、単一金ナノディスクをナノ共振器に結合させた状態をシミュレーションし、その分裂エネルギーから得られる空間のサイズを求めた。その結果、別途求めた金ナノディスクの消光断面積などと比較して一桁程度大きな値が得られ、この空間に存在する金ナノディスクが共振器と空間的にコヒーレントに結合するコヒーレンスエリアとなっていると推論している。さらに、フェムト秒過渡吸収測定から結合強度を増強させると、非強結合電極では見られない金から酸化チタンへの電子注入が増強されることを実験的に検証した。 また、金-銀合金ナノ粒子を用いてナノ共振器と結合させたところ結合強度が金の場合に比べて2倍程度増強し、「超強結合」となることを明らかにした。さらに、本超強結合電極を用いて水を電子源とする光電流を測定したところ、金と比べて2倍程度増強されること、またフェムト秒過渡吸収より金から酸化チタンへの電子注入が増強していることを明らかにした。 さらに、強結合電極の最適化を図るため、水の酸化反応の助触媒としてコバルト酸化物を金ナノ粒子の近傍に空間選択的に形成させ、反応効率を2倍以上増強することに成功した。また、キノコ型の金ナノ粒子を用いて近接場の空間制御を行い、反応効率を30%増強することにも成功した。
  • フォトニック結晶と結合する局在プラズモンを用いた光アンモニア合成
    日本学術振興会:科学研究費助成事業 基盤研究(A)
    研究期間 : 2017年04月 -2019年03月 
    代表者 : 三澤 弘明
     
    金ナノ微粒子が示す局在プラズモン共鳴を利用し、水を電子源として空中窒素からアンモニアを高効率に合成するためには、入射光を極めて高い効率で金ナノ微粒子に吸収させることが可能な光アノードの開発が必要不可欠である。前年度までに、可視光の閉じ込め機能を有する酸化チタン逆オパールフォトニック結晶中に局在プラズモン共鳴を示す金ナノ微粒子を担持させた光アノードの作製に成功している。平成30年度はフォトニック結晶のストップバンドモードとプラズモンモードをより強く結合させるため、フォトニック結晶中に担持する金ナノ微粒子のサイズや、空間分布を電気化学的手法を用いて制御する方法論の開発に取り組んだ。作製した酸化チタン逆オパールフォトニック結晶構造をカソードとし、それを塩化金酸を加えた電解質水溶液中に浸漬して電解還元により金ナノ微粒子をフォトニック結晶表面に担持した。定電流電解によって担持した金ナノ微粒子のサイズは数ナノメーターと小さく、局在プラズモンバンドがフォトニック結晶のストップバンドモードよりも短波長側に生じたため十分な強結合状態は得られなかった。大きな金ナノ微粒子を形成させて局在プラズモンモードをより長波長側に出現させるため、パルス電流を用いて電解還元を行ったところ、パルス形状により粒径が10数ナノメーターの金ナノ微粒子が生成し、フォトニック結晶のストップバンドモードとプラズモンモードのより強い強結合状態が形成することを見出した。一方、フォトニック結晶と同様に光閉じ込め効果を有するナノ共振器をn型半導体である酸化チタン薄膜とp型半導体である酸化ニッケル薄膜を接合させ、さらにその接合面に金ナノ微粒子を配置して形成させ、太陽電池構造を作製したところ、照射光波長によって電流の流れる向きが反転するスイッチ現象が現れることも見出し論文として報告した。
  • 可視・近赤外光による光アンテナ搭載完全水分解システム
    日本学術振興会:科研費 新学術領域研究 研究領域提案型(公募)
    研究期間 : 2015年04月 -2017年03月 
    代表者 : 三澤 弘明
  • 高効率な光捕集・局在化を可能にする光アンテナの開発とその太陽電池への応用
    日本学術振興会:科研費 基盤研究(S)
    研究期間 : 2011年04月 -2016年03月 
    代表者 : 三澤 弘明
  • 可視・近赤外局在プラズモンによる水の完全分解システムの構築
    日本学術振興会:科研費 新学術領域研究 研究領域提案型(公募)
    研究期間 : 2013年04月 -2015年03月 
    代表者 : 三澤 弘明
  • 原子スケールで制御された金属ナノ接合における電子伝導の光制御
    科学技術振興機構:戦略的国際科学技術協力推進事業
    研究期間 : 2009年04月 -2012年03月 
    代表者 : 三澤 弘明
  • 金属ナノ構造を用いた光局在場の創製と光科学反応への応用
    文部科学省:科研費 特定領域研究(計画班)
    研究期間 : 2007年07月 -2011年03月 
    代表者 : 三澤 弘明
  • 光-分子強結合反応場の創成
    文部科学省:科研費 特定領域研究(総括班)
    研究期間 : 2007年07月 -2011年03月 
    代表者 : 三澤 弘明
  • 金属ナノ周期構造を用いた高感度DNAアレイチップの開発
    日本学術振興会:科研費 基盤研究(B)
    研究期間 : 2005年04月 -2008年03月 
    代表者 : 三澤 弘明
  • 量子相関光子ビームナノ加工
    科学技術振興機構:戦略的基礎研究推進事業(CREST)
    研究期間 : 2003年04月 -2007年03月 
    代表者 : 三澤 弘明
  • 光の放射圧を利用したナノアクチュエーターの開発
    日本学術振興会:科研費 基盤研究(A)(一般)(2)
    研究期間 : 2001年04月 -2004年03月 
    代表者 : 三澤 弘明
  • 三次元光メモリー
  • 微小領域の光物理・化学現象に関する研究
  • マイクロマシンに関する研究
  • Study on Three-dimensional Optical Memory
  • Study on Photophysics and Photochemistry in a Small Domain
  • Study on Micromachine

教育活動情報

主要な担当授業

  • ナノフォトニクス特論
    開講年度 : 2021年
    課程区分 : 修士課程
    開講学部 : 情報科学研究科
    キーワード : ナノフォトニクス,プラズモンポラリトン,レーザーマニピュレーション,顕微分光,ナノ加工/計測
  • ナノフォトニクス特論
    開講年度 : 2021年
    課程区分 : 修士課程
    開講学部 : 情報科学院
    キーワード : ナノフォトニクス,プラズモンポラリトン,レーザーマニピュレーション,顕微分光,ナノ加工/計測
  • ナノフォトニクス特論
    開講年度 : 2021年
    課程区分 : 博士後期課程
    開講学部 : 情報科学研究科
    キーワード : 神経科学,記憶・学習, 光学イメージング,脳機能計測, 深層学習, 人工知能
  • ナノフォトニクス特論
    開講年度 : 2021年
    課程区分 : 博士後期課程
    開講学部 : 情報科学院
    キーワード : ナノフォトニクス,プラズモンポラリトン,レーザーマニピュレーション,顕微分光,ナノ加工/計測

大学運営

委員歴

  • 2015年01月 - 現在   国立交通大学(台湾)   客員教授
  • 2014年05月 - 現在   日本化学会   ディビジョン運営委員会 ディビジョン主査
  • 2014年05月 - 現在   日本化学会   プログラム小委員会 部門幹事
  • 2014年01月 - 現在   光化学協会   会長
  • 2014年01月 - 現在   ACS Photonics   Editorial Advisory Board
  • 2014年01月 - 現在   光化学協会   理事
  • 2013年05月 - 現在   Asian Nanoscience Nanotechnology Association   President
  • 2012年07月 - 現在   Nanotechnology Innovation Center for Environment & Ecosystem   Academic Committee
  • 2012年01月 - 現在   独立行政法人理化学研究所   客員主幹研究員
  • 2011年10月 - 現在   日本学術会議   連携会員
  • 2011年05月 - 現在   独立行政法人科学技術振興機構 戦略的創造研究推進事業   研究領域「元素戦略を基軸とする物質・材料の革新的機能の創出」領域アドバイザー
  • 2008年08月 - 現在   独立行政法人日本学術振興会   先端科学(FoS)シンポジウム事業委員会 専門委員   2005.3.1〜2006.6.28 同上
  • 2006年04月 - 現在   文部科学省 科学技術政策研究所 科学技術動向研究センター   専門調査委員
  • 2013年02月 - 2015年03月   石狩超電導直流送電プロジェクト推進協議会   構成員
  • 2012年04月 - 2015年03月   独立行政法人日本学術振興会   学術システム研究センターセンター研究員
  • 2008年05月 - 2015年03月   独立行政法人科学技術振興機構 戦略的創造研究推進事業   研究領域「光の利用と物質材料・生命機能」領域アドバイザー
  • 2012年03月 - 2014年02月   文部科学省   「低炭素社会構築に向けた研究基盤ネットワーク整備」運営会議委員   2010.7.20-2011.3.31も同上
  • 2010年07月 - 2013年12月   European Research Council   Peer Reviewer
  • 2010年02月 - 2013年12月   Journal of Photochemistry and Photobiology C, Photochemistry Review   Deputy Editor
  • 2012年 - 2013年03月   第11回ナノテクノロジー総合シンポジウムプログラム委員
  • 2011年05月 - 2013年03月   独立行政法人新エネルギー・産業技術総合開発機構   NEDO技術委員
  • 2010年01月 - 2012年12月   Journal of Physical Chemistry   Advisory Board Member
  • 2011年10月 - 2012年03月   第10回ナノテクノロジー総合シンポジウムプログラム委員
  • 2011年08月 - 2012年03月   独立行政法人日本学術振興会   特別研究員等審査会専門委員及び国際事業委員会書面審査員
  • 2010年04月 - 2012年02月   日本化学会   学術活性化委員会委員
  • 2010年01月 - 2011年12月   光化学協会   理事
  • 2010年07月 - 2011年07月   LPM2011国際顧問委員会   委員   (A member of the International Advisory Committee of LPM 2011)
  • 2010年11月 - 2011年03月   第9回ナノテクノロジー総合シンポジウム委員
  • 2009年01月 - 2010年12月   ACS APPLIED MATERIALS&INTERFACES   EDITORIAL ADVISORY BOARD
  • 2008年12月 - 2010年11月   独立行政法人日本学術振興会   科学研究費委員会専門委員   2006.1.1〜2006.12.31 同上 2002 同上
  • 2009年03月 - 2010年03月   電子情報通信学会 超高速光エレクトニクス研究会   専門委員   2007.3.12〜2007.12.31 同上
  • 2008年03月 - 2010年02月   日本化学会北海道支部   幹事
  • 2007年12月 - 2010年01月   文部科学省   科学技術・学術審議会 専門委員
  • 2007年03月 - 2009年11月   TNANO (IEEE Transactions on Nanotechnology)   Associate Editor
  • 2008年07月 - 2009年03月   文部科学省   「元素戦略プロジェクト」審査委員会 外部専門家
  • 2007年06月 - 2009年03月   文部科学省   ナノテクノロジー・ネットワーク運営委員会委員
  • 2008年02月 - 2008年02月   首都大学東京教員選考委員会   委員
  • 2006年01月 - 2007年12月   光化学協会   常任理事
  • 2007年11月 - 2007年11月   The 20th Korea Joint Forum 2008   Scientific Committee Member
  • 2006年12月 - 2007年03月   NEDOナノテクノロジーロードマップ「ナノインプリント・精密ビーム加工」   WG主査
  • 2006年03月 - 2007年02月   独立行政法人日本学術振興会   先端科学(FoS)シンポジウム事業委員会 専門委員
  • 2006年01月 - 2006年03月   古河テクノリサーチ株式会社   NEDO平成17年度委託事業 有識者委員会 委員
  • 2004年07月 - 2005年03月   財団法人光産業技術振興会   平成16年フェムト秒超加工技術フィージビリティ調査委員会 委員
  • 2004年04月 - 2005年03月   独立行政法人日本学術振興会   第7回日米先端科学(JAFoS)シンポジウム2004 Planning Group Member 主査
  • 2004年04月 - 2005年03月   社団法人高温学会   レーザー加工学会査読委員会 査読委員
  • 2004年04月 - 2005年03月   財団法人光技術振興協会   平成16年フェムト秒超加工研究会 幹事   2001年 同上
  • 2004年 - 2004年   LPM2004 国際会議 The 5th International Symposium on Laser Precision Microfabrication   Organizing Committee Member
  • 2002年 - 2002年   財団法人光産業技術振興協会主催   「平成13年度光技術海外動向調査事業」動向調査団長
  • 2002年 - 2002年   社団法人日本セラミックス協会   「平成14年度セラミックスインテグレーション技術による新機能材料創製に関する研究」バッファーレイヤー調査研究委員会 委員
  • 2002年 - 2002年   財団法人光産業技術振興協会   平成14年度光産業構造中長期展望専門委員会技術分科会委員
  • 2002年   NEDO 新エネルギー産業技術総合開発機構   評価委員
  • 2002年   科学技術振興事業団   地域結集型共同研究事業中間評価専門委員   科学技術振興事業団
  • 2001年 - 2001年   2001 Photonic West (OSA)   LASEプログラム委員
  • 2001年 - 2001年   レーザー学会   第22回年次大会プログラム委員
  • 2001年 - 2001年   CLEO / PR 2001   プログラム委員会委員
  • 2001年 - 2001年   文部科学省 科学技術政策所   科学技術専門家ネットワーク専門調査員
  • 2001年   社団法人電気学会   論文委員会 委員
  • 2001年   (社)電気学会   論文委員会委員   (社)電気学会
  • 2000年   社団法人電子情報通信学会   レーザ・量子エレクトロニクス研究会専門委員
  • 2000年   第14回日本エム・イー学会   秋季大会プログラム委員
  • 2000年   財団法人フォトンセンター   研究動向調査委員会 委員
  • 2000年   財団法人光産業技術振興協会   技術動向調査委員会 委員
  • 1999年 - 1999年   財団法人四国産業・技術振興センター   医工融合領域フロンティア研究会委員
  • 1999年 - 1999年   財団法人マイクロマシンセンター   マイクロ流体システム調査委員会委員
  • 1996年 - 1998年   財団法人四国産業・技術振興センター   テクノサロン運営委員会メカトロニクス委員会 委員
  • 1987年 - 1997年   財団法人四国産業・技術振興センター   四国地域における新規産業創出支援機能に関する医療・福祉専門委員会 委員
  • 1995年   日本機械学会   設計工学・システム部門運営委員,トピックス委員会委員   日本機械学会
  • 1987年 - 1990年   日本化学会   トッピクス小委員会委員   日本化学会


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