橋谷田　俊 (ハシヤダ　シユン)

電子科学研究所　光科学研究部門助教
Last Updated :2025/05/02

■研究者基本情報

学位

  • 博士（理学）, 総合研究大学院大学, 2017年03月

Researchmap個人ページ

ホームページURL

J-Global ID

研究キーワード

  • 電磁キラリティ（LipkinのZilch）
  • 軌道角運動量
  • スピン角運動量
  • 光の角運動量
  • らせん光二色性
  • 光渦二色性
  • 円二色性
  • 光渦
  • 円偏光発光
  • 偏光解析
  • 光物性
  • ナノ光学
  • ナノ構造体
  • 光学活性
  • キラリティ
  • 近接場光学顕微鏡
  • プラズモン
  • 物理化学

研究分野

  • ナノテク・材料, 応用物理一般
  • ナノテク・材料, 分析化学
  • 自然科学一般, 数理物理、物性基礎
  • ナノテク・材料, 基礎物理化学
  • 自然科学一般, 半導体、光物性、原子物理

担当教育組織

■経歴

経歴

  • 2023年04月 - 現在
    北海道大学, 電子科学研究所, 助教
  • 2022年04月 - 2023年03月
    中央大学, 科研費研究員
  • 2019年04月 - 2022年03月
    理化学研究所, 基礎科学特別研究員
  • 2019年06月 - 2019年06月
    University of Glasgow, School of Chemistry, Visiting Researcher
  • 2017年04月 - 2019年03月
    分子科学研究所, 博士研究員
  • 2015年04月 - 2017年03月
    日本学術振興会, 特別研究員 （DC2）
  • 2016年07月 - 2016年08月
    University of Glasgow, School of Chemistry, Visiting Student
  • 2015年11月 - 2015年12月
    University of Glasgow, School of Chemistry, Visiting Student
  • 2014年10月 - 2015年03月
    分子科学研究所, 特別奨学生
  • 2014年09月 - 2014年12月
    University of Glasgow, School of Chemistry, Visiting Student

学歴

  • 2012年04月 - 2017年03月, 総合研究大学院大学, 物理科学研究科, 構造分子科学専攻
  • 2007年04月 - 2011年03月, 防衛大学校, 理工学専攻, 応用物理学科

■研究活動情報

受賞

  • 2017年09月, 総合研究大学院大学, 総合研究大学院大学研究賞　　　　　　　　　　　　　　　
    橋谷田 俊
  • 2016年10月, Student Award, OSJ-OSA Joint Symposia on Plasmonics and Digital Photonics　　　　　　　　　　　　　　　
  • 2016年09月, The Best Poster Presentation Award, The 14th International Conference on Near-Field Optics, Nanophotonics and Related Techniques (NFO-14)　　　　　　　　　　　　　　　
    橋谷田 俊, 国際学会・会議・シンポジウム等の賞
  • 2015年10月, 第9回分子科学討論会 優秀ポスター賞　　　　　　　　　　　　　　　
    橋谷田 俊, 国内学会・会議・シンポジウム等の賞, 日本国
  • 2015年04月, 日本化学会, 第95春季年会(2015)学生講演賞　　　　　　　　　　　　　　　
    橋谷田 俊, 国内学会・会議・シンポジウム等の賞
  • 2014年03月, 日本化学会, 東海支部長賞　　　　　　　　　　　　　　　
    橋谷田 俊, 国内学会・会議・シンポジウム等の賞
  • 2014年02月, Asian CORE Winter School, Outstanding Oral Award 2014　　　　　　　　　　　　　　　
    橋谷田 俊, 国際学会・会議・シンポジウム等の賞
  • 2013年11月, 日本光学会, 第9回OPJ ベストプレゼンテーション賞　　　　　　　　　　　　　　　
    橋谷田 俊, 国内学会・会議・シンポジウム等の賞

論文

  • Conservation law for angular momentum based on optical field derivatives: Analysis of optical spin-orbit conversion
    Shun Hashiyada, Yoshito Y. Tanaka
    arXiv, 2024年10月, ［筆頭著者, 責任著者］
  • Rapid modulation of left- and right-handed optical vortices for precise measurements of helical dichroism
    Shun Hashiyada, Yoshito Y. Tanaka
    Review of Scientific Instruments, 95, 5, 053101, AIP Publishing, 2024年05月01日, ［査読有り］, ［筆頭著者, 責任著者］
    研究論文（学術雑誌）, Helical dichroism (HD), which is defined as the difference in optical absorption between chiral pairs of lights involving left-handed (LH) and right-handed (RH) optical vortices (OVs) carrying orbital angular momentum (OAM), is a promising way to characterize chiral materials. In the current major methods of OV generation using spatial light modulators (SLMs), the speed of OAM switching is typically as slow as 100 Hz, which is comparable to low-frequency noise, making precise chiral detection difficult. Here, we theoretically propose and experimentally demonstrate a rapid modulation of the LH and RH OVs at around 50 kHz. This modulation is achieved through a rapid modulation of circularly polarized lights carrying spin angular momentum (SAM), combined with a SAM–OAM conversion technique. We establish a theory not only for rapid OV modulation but also for HD measurements using the modulated OVs. We experimentally verify the theory using helical phase holograms drawn on a SLM as a pseudo-HD active sample. Our work addresses the limitations of current methods and offers a new avenue for precise HD measurements, paving the way for the development of sensitive chiral-optical spectroscopy techniques.
  • Circular dichroism of pseudo-two-dimensional metal nanostructures: Rotational symmetry and reciprocity
    Kensaku Endo, Shun Hashiyada, Tetsuya Narushima, Yoshihiko Togawa, Hiromi Okamoto
    The Journal of Chemical Physics, 159, 23, AIP Publishing, 2023年12月19日, ［査読有り］
    英語, 研究論文（学術雑誌）, Circular dichroism (CD) spectra for pseudo-two-dimensional chiral nanomaterials were systematically investigated and analyzed in relation to the rotational symmetry of the nanomaterials. Theoretically, an ideal two-dimensional chiral matter is CD inactive for light incident normal to the plane if it possesses threefold or higher rotational symmetry. If the matter has two- or onefold rotational symmetry, it should exhibit CD activity, and the CD signal measured from the back side of the matter is expected to be inverted from that measured from the front side. For pseudo-two-dimensional chiral gold nanostructures fabricated on glass substrates using electron beam lithography, matter with fourfold rotational symmetry is found to be CD active, even when special care is taken to ensure that the optical environments for the front and back sides of the sample are equivalent. In this case, the CD signal measured from the back side is found to be almost exactly the same as that measured from the front side. It is revealed that the observed chiro-optical behavior arises from three-dimensional chiral characteristics due to differences in the surface shape between the front and back sides of the structures. For matter that is two- or onefold rotationally symmetric, the CD signal measured from the back side is not coincident with that from the front side. For certain wavelength regions, the CD signals measured from the front side and back side are observed to be similar, while at other wavelengths, the inverted component of the CD signals is found to dominate. The observed CD spectral behavior for reciprocal optical measurement configurations is considered to be determined by a balance between the in-plane isotropic and anisotropic components of the chiral permittivity.
  • Near-Field Probing of Optical Superchirality with Plasmonic Circularly Polarized Luminescence for Enhanced Bio-Detection
    Victor Tabouillot, Rahul Kumar, Paula L. Lalaguna, Maryam Hajji, Rebecca Clarke, Affar S. Karimullah, Andrew R. Thomson, Andrew Sutherland, Nikolaj Gadegaard, Shun Hashiyada, Malcolm Kadodwala
    ACS Photonics, American Chemical Society (ACS), 2022年10月20日, ［査読有り］
    研究論文（学術雑誌）
  • Optical gradient force on chiral particles
    Junsuke Yamanishi, Hyo-Yong Ahn, Hidemasa Yamane, Shun Hashiyada, Hajime Ishihara, Ki Tae Nam, Hiromi Okamoto
    Science Advances, 8, 38, eabq2604, American Association for the Advancement of Science (AAAS), 2022年09月23日, ［査読有り］, ［国際誌］
    英語, 研究論文（学術雑誌）, When a chiral nanoparticle is optically trapped using a circularly polarized laser beam, a circular polarization (CP)–dependent gradient force can be induced on the particle. We investigated the CP-dependent gradient force exerted on three-dimensional chiral nanoparticles. The experimental results showed that the gradient force depended on the handedness of the CP of the trapping light and the particle chirality. The analysis revealed that the spectral features of the CP handedness–dependent gradient force are influenced not only by the real part of the refractive index but also by the electromagnetic field perturbed by the chiral particle resonant with the incident light. This is in sharp contrast to the well-known behavior of the gradient force, which is governed by the real part of the refractive index. The extended aspect of the chiral optical force obtained here can provide novel methodologies on chirality sensing, manipulation, separation, enantioselective biological reactions, and other fields.
  • Optical gradient force on Chiral nanoparticles
    Junsuke Yamanishi, Hyo-Yong Ahn, Shun Hashiyada, Hiromi Okamoto
    Proceedings of SPIE - The International Society for Optical Engineering, 11522, SPIE, 2020年
    英語, 研究論文（国際会議プロシーディングス）, Optical trapping of nanoparticles is realized by optical gradient force originated from the intensity gradient of light with a focused beam. It is expected that the gradient force depending on the circular polarization (CP) acts on particles with chiral structures. Here, we investigate the CP-dependent gradient force on the chiral gold nanoparticles. We found that the amplitude (dispersion of the position of the Brownian motion) depends on the handedness of the incident light in both cases of D- and L-form particles. Based on the results on the gradient force for the chiral particles, it is expected that chiral nanomaterials can be handled by the circularly polarized light.
  • Roles of superchirality and interference in chiral plasmonic biodetection
    Cameron Gilroy, Shun Hashiyada, Kensaku Endo, Affar Shahid Karimullah, Laurence D. Barron, Hiromi Okamoto, Yoshihiko Togawa, Malcolm Kadodwala
    The Journal of Physical Chemistry C, 123, 24, 15195, 15203, AMER CHEMICAL SOC, 2019年05月, ［査読有り］, ［責任著者］
    英語, 研究論文（学術雑誌）, Chiral plasmonic nanostructures enable <= pg detection and characterization of biomaterials. The sensing capabilities are associated with the chiral asymmetry of the near fields, which locally can be greater than equivalent circularly polarized light, a property referred to as superchirality. However, sensing abilities do not simply scale with the magnitude of superchirality. We show that chiral molecular sensing is correlated to the thickness of a nanostructure. This observation is reconciled with a previously unconsidered interference mechanism for the sensing phenomenon. It involves the "dissipation" of optical chirality into chiral material currents through the interference of fields generated by two spatially separated chiral modes. The presence of a chiral dielectric causes an asymmetric change in the phase difference, resulting in asymmetric changes to chiroptical properties. Thus, designing a chiral plasmonic sensor requires engineering a substrate that can sustain both superchiral fields and an interference effect.
  • Spectral properties of chiral electromagnetic near fields created by chiral plasmonic nanostructures
    Shun Hashiyada, Kensaku Endo, Tetsuya Narushima, Yoshihiko Togawa, Hiromi Okamoto
    Journal of Physics: Conference Series, 1220, 1, 012050, 2019年05月, ［査読有り］, ［筆頭著者, 責任著者］
    英語, 研究論文（国際会議プロシーディングス）, © Published under licence by IOP Publishing Ltd. The surface-enhanced chiral-optical spectroscopy is based on the interaction of chiral molecules with chiral electromagnetic near field localized on a chiral plasmonic nanostructure. It is of fundamental importance to reveal the spectral characteristics of chiral near fields for maximizing the chiral interaction. Here we investigate relations between near field and far field polarization characteristics of the chiral plasmonic nanostructures, using electromagnetic simulations. We found that spectral features of chiral near fields created by the nanostructures intercorrelate with those of far field optical rotation. This finding may provide us a method to characterize and design the chiral near field.
  • Active control of chiral optical near fields on a single metal nanorod
    Shun Hashiyada, Tetsuya Narushima, Hiromi Okamoto
    ACS Photonics, 6, 3, 677, 683, AMER CHEMICAL SOC, 2019年01月, ［査読有り］, ［筆頭著者, 責任著者］
    英語, 研究論文（学術雑誌）, Chiral optical fields (typified by circularly polarized light) localized on the nanoscale enhance the chiral light-matter interaction, which may provide novel potential applications. This property enables the development of an ultrasensitive method for characterization of chiral molecules and nanoscale magnetic control realized by an all-optical method to interconnect spintronic nano-optical devices. A local chiral light source with switchable handedness or controllable chirality is indispensable for building such applications for practical use. In the current major method used for local chiral light generation, the handedness of the light is controlled by the handedness of the nanomaterial, which is not convenient when we need to change the handedness of the light. We experimentally achieve here generation and active control of a highly chiral local optical field by using a combination of an achiral gold nanorod and achiral linearly polarized optical field. By tilting the azimuth angle for the incident linear polarization relative to the axis of the nanorod, either left- or right-handed circularly polarized local optical fields can be generated. Our work may give us a chance to pioneer analytical applications of chiral optical fields and novel spintronic nano-optical devices.
  • Circularly polarized photoluminescence from achiral dye molecules induced by plasmonic two-dimensional chiral nanostructures
    Khai Q Le, Shun Hashiyada, Masaharu Kondo, Hiromi Okamoto
    The Journal of Physical Chemistry C, 122, 43, 24924, 24932, American Chemical Society (ACS), 2018年10月, ［査読有り］
    英語, 研究論文（学術雑誌）
  • Nanoscale chiral surface relief of azo-polymers with nearfield OAM light
    Keigo Masuda, Ryo Shinozaki, Yoshinori Kinezuka, Junhyung Lee, Seigo Ohno, Shun Hashiyada, Hiromi Okamoto, Daisuke Sakai, Kenji Harada, Katsuhiko Miyamoto, Takashige Omatsu
    Optics Express, 26, 17, 22197, 22207, The Optical Society, 2018年08月, ［査読有り］
    英語, 研究論文（学術雑誌）
  • 場の語りがもたらす双方向の科学技術コミュニケーション
    奥本素子, 橋谷田俊, 高橋明大, 阿部乳坊
    科学教育研究, 42, 131, 139, 2018年07月, ［査読有り］
    日本語, 研究論文（学術雑誌）
  • Imaging Chirality of Optical Fields near Achiral Metal Nanostructures Excited with Linearly Polarized Light
    Shun Hashiyada, Tetsuya Narushima, Hiromi Okamoto
    ACS Photonics, 5, 4, 1486, 1492, American Chemical Society, 2018年04月18日, ［査読有り］, ［筆頭著者］
    英語, 研究論文（学術雑誌）, Chiral systems (consisting of materials and incident radiation) respond differently to left- and right-handed circularly polarized light macroscopically. As a consequence, only chiral materials show intrinsic macroscopic optical activity, and only chiral systems generate circularly polarized light from linearly polarized incident light. In the nanoscopic regime, in contrast to this general rule for macroscopic cases, it is theoretically expected that achiral (nonchiral) systems can locally generate circularly polarized fields. Here, we report experimental evidence for that situation in achiral systems consisting of gold nanostructures and linearly polarized incident light. The local circularly polarized fields were visualized by near-field polarimetry imaging, and the spatial features of the observed circularly polarized fields were qualitatively reproduced by a simple dipole model. The present results may provide a novel technique to produce controllable circularly polarized optical fields in nanospaces.
  • Optical Activity Governed by Local Chiral Structures in Two-Dimensional Curved Metallic Nanostructures
    Tetsuya Narushima, Shun Hashiyada, Hiromi Okamoto
    CHIRALITY, 28, 7, 540, 544, WILEY-BLACKWELL, 2016年07月, ［査読有り］
    英語, 研究論文（学術雑誌）, Chiral nanostructures show macroscopic optical activity. Local optical activity and its handedness are not uniform in the nanostructure, and are spatially distributed depending on the shape of the nanostructure. In this study we fabricated curved chain nanostructures made of gold by connecting linearly two or more arc structures in a two-dimensional plane. Spatial features of local optical activity in the chain structures were evaluated with near-field circular dichroism (CD) imaging, and analyzed with the aid of classical electromagnetic simulation. The electromagnetic simulation predicted that local optical activity appears at inflection points where arc structures are connected. The handedness of the local optical activity was dependent on the handedness of the local chirality at the inflection point. Chiral chain structures have odd inflection points and the local optical activity distributed symmetrically with respect to structural centers. In contrast, achiral chain structures have even inflection points and showed antisymmetric distribution. In the near-field CD images of fabricated chain nanostructures, the symmetric and antisymmetric distributions of local CD were observed for chiral and achiral chain structures, respectively, consistent with the simulated results. The handedness of the local optical activity was found to be determined by the handedness of the inflection point, for the fabricated chain structures having two or more inflection points. The local optical activity was thus governed primarily by the local chirality of the inflection points for the gold chain structures. The total effect of all the inflection points in the chain structure is considered to be a predominant factor that determines the macroscopic optical activity. (C) 2016 Wiley Periodicals, Inc.
  • Local Optical Activity in Achiral Two-Dimensional Gold Nanostructures
    Shun Hashiyada, Tetsuya Narushima, Hiromi Okamoto
    JOURNAL OF PHYSICAL CHEMISTRY C, 118, 38, 22229, 22233, AMER CHEMICAL SOC, 2014年09月, ［査読有り］, ［筆頭著者］
    英語, 研究論文（学術雑誌）, Since Pasteur's discovery of molecular chirality, which means that the molecule has a nonsuperposable mirror image, the geometrical chirality of a material has been considered the prerequisite for exhibiting circular dichroism (CD, defined as the differential absorption of left and right circularly polarized light) of the structural origin. Here, we report an experimental demonstration of nanoscale local CD activities for achiral (nonchiral) rectangular gold nanostructures. Macroscopic CD spectral measurements of the nanostructure sample did not show any CD activity over the entire range of measured wavelengths, as expected from the achiral shape of the rectangle. In contrast, we found both locally positive and negative CD signals in a single rectangular nanostructure, whose distribution was symmetric about the center of the rectangle, with large CD signals at the corners. The results demonstrate that the established selection rule of optical activity is not valid for local microscopic measurements.
  • Nanoscopic Study on Developing Optical Activity with Increasing Chirality for Two-Dimensional Metal Nanostructures
    Tetsuya Narushima, Shun Hashiyada, Hiromi Okamoto
    ACS PHOTONICS, 1, 8, 732, 738, AMER CHEMICAL SOC, 2014年08月, ［査読有り］
    英語, 研究論文（学術雑誌）, We studied the correlation between the geometry and the local optical activity of an "S"-shaped chiral nanostructure composed of two associating achiral "C"-shaped partial structures as one way to elucidate how optical activity develops with the formation of a chiral structure. This chirality formation process models the formation of chiral molecules by association of achiral atoms or functional groups. The local optical activities induced by the association of the achiral nanostructures were investigated using a circular dichroism (CD) nanoimaging technique. The chirality formed with the two approaching achiral partial structures caused enhancement of the local optical activity around the region of their connection when the distance between the achiral partial structures was less than 350 nm. The local optical activity was enhanced even without physical contact of the two partial structures. We therefore concluded that long-range electromagnetic interaction, rather than electronic exchange between the two partial structures, made a major contribution to the optical activity of the chiral nanostructure.
  • 2次元金属ナノ構造体が示す強い局所光学活性：近接場円二色性イメージング
    成島 哲也, 橋谷田 俊, 岡本 裕巳
    表面科学, 35, 6, 312, 318, 公益社団法人 日本表面科学会, 2014年06月, ［査読有り］
    日本語, 研究論文（学術雑誌）, Nanostructures with chiral shapes show optical activity. The optical activity of the chiral nanostructure may be regarded approximately as an integration of contributions from optical activity of local sites over the entire nanostructure. In this article, we describe our recent experimental efforts to realize 100-nm-scale spatially resolved circular dichroism (CD) imaging. The results of CD imaging for S-shaped gold nanostructure are compared with the macroscopically obtained CD spectra. Local CD signals of both handednesses coexisted in the individual nanostructure, and the spatial distribution of the CD reflected the chiral symmetry of the nanostructure. When the local CD signal is integrated over the entire nanostructure, its value was approximately 1% of the maximum local CD signal, which roughly coincided with the macroscopic CD signal. This indicates that there are possibly prominent local CD signals even if only a tiny CD signal is observed in the macroscopic measurements of optical activity for nanostructured samples.

その他活動・業績

  • キラル光学応答
    橋谷田俊, 岡本裕巳, 固体物理, 59, 11, 79, 94, 2024年11月, ［査読有り］, ［招待有り］, ［筆頭著者, 責任著者］, ［国内誌］
    This article reviews the history and development of chirality in materials and light, highlighting key discoveries, the role of polarized light, and advancements in chiral optical responses. It covers fundamental principles and explores advanced research on chiral optical responses to circularly polarized light, chiral optical near­field, and optical
    vortices., アグネ技術センター, 日本語, 記事・総説・解説・論説等（その他）
  • Spectral properties of chiral electromagnetic near fields created by chiral plasmonic nanostructures
    Shun Hashiyada, Kensaku Endo, Tetsuya Narushima, Yoshihiko Togawa, Hiromi Okamoto, 2018 Joint Symposia on Optics (Optical Society of America, 2018), paper 30aCJ4, Part F125-OPJ 2018, 2018年10月
    © 2018 OSJ We investigate relations between near field and far field polarization characteristics of the chiral plasmonic nanostructures, using electromagnetic simulations. We found that the spectral features of chiral near fields created by the nanostructures intercorrelate with those of far field optical rotation. This finding may provide us a method to characterize the chiral near field., 英語, 記事・総説・解説・論説等（国際会議プロシーディングズ）
  • Active polarization control of optical fields localized on gold nano-rectangles
    Shun Hashiyada, Tetsuya Narushima, Hiromi Okamoto, Proceedings of SPIE - The International Society for Optical Engineering, 10712, 107121S, 2018年
    We demonstrate here that control of local optical field near a single non-chiral gold nano-rectangle irradiated with linearly polarized light is possible from linearly polarized to nearly pure left- or right-handed circular polarization, by adjusting the angle of the incident polarization relative to the rectangle., SPIE, 英語, 記事・総説・解説・論説等（国際会議プロシーディングズ）
  • Imaging Chiral Plasmons
    Hiromi Okamoto, Shun Hashiyada, Yoshio Nishiyama, Tetsuya Narushima, SAP-OSA Joint Symposia 2017 Abstracts (Optical Society of America, 2017), paper 5a_A410_1, Part F78-JSAP 2017, 2017年09月
    英語, 記事・総説・解説・論説等（国際会議プロシーディングズ）
  • Generation of Chiral Optical Near-Fields with Non-Chiral Metallic Nanostructures and Linearly Polarized Light
    Shun Hashiyada, Tetsuya Narushima, Hiromi Okamoto, OPTICAL MANIPULATION CONFERENCE, 10252, 1025214, 2017年
    We experimentally demonstrate that non-chiral plasmonic nanostructured materials interacting with linearly polarized (non-chiral) light generate elliptically polarized (chiral) optical near-fields in local nano spaces around the materials., SPIE-INT SOC OPTICAL ENGINEERING, 英語, 記事・総説・解説・論説等（国際会議プロシーディングズ）

講演・口頭発表等

担当経験のある科目_授業

  • 生体情報工学実験II（キラル分子の旋光性）　　　　　　　　　　　　　　　
    北海道大学
  • 一般教育演習(ﾌﾚｯｼｭﾏﾝｾﾐﾅｰ) 暮らしの中のサイエンス（キラリティの科学）　　　　　　　　　　　　　　　
    北海道大学
  • 情報エレクトロニクス演習　　　　　　　　　　　　　　　
    北海道大学
  • ナノフォトニクス特論　　　　　　　　　　　　　　　
    北海道大学

所属学協会

  • 2024年04月 - 現在
    日本光学会　　　　　　　　　　　　　　　
  • 応用物理学会　　　　　　　　　　　　　　　
  • 分子科学会　　　　　　　　　　　　　　　
  • 日本物理学会　　　　　　　　　　　　　　　

共同研究・競争的資金等の研究課題

  • キラル縦偏光の創出と物質キラリティ検出
    科学研究費助成事業
    2023年04月 - 2026年03月
    橋谷田 俊
    日本学術振興会, 基盤研究(C), 北海道大学, 研究代表者, 23K04669
  • 禁制光検出による迅速なキラル近接場光スペクトル測定法の開発　　　　　　　　　　　　　　　
    科研費（若手研究）
    2021年04月 - 2023年03月
    日本学術振興会, 研究代表者
  • キラル磁気プラズモニクスの開拓　　　　　　　　　　　　　　　
    先端光科学研究プロジェクト
    2021年08月 - 2022年03月
    橋谷田俊 戸川欣彦
    自然科学研究機構新分野創成センター, 研究代表者
  • プラズモン光ピンセットで捕捉した分子のキラル分光分析　　　　　　　　　　　　　　　
    科研費（若手研究）
    2019年04月 - 2021年03月
    橋谷田 俊
    日本学術振興会, 研究代表者, 競争的資金
  • 対称金属ナノ構造と直線偏光を用いた不斉分子の高感度検出　　　　　　　　　　　　　　　
    科研費（研究活動スタート支援）
    2017年08月 - 2019年03月
    橋谷田 俊
    日本学術振興会, 研究代表者, 競争的資金
  • キラルなプラズモン励起による不斉光化学場の展開
    科学研究費助成事業
    2015年04月 - 2019年03月
    岡本 裕巳, 成島 哲也, 西山 嘉男, 橋谷田 俊, レ カイ クヮン, カドドワラ マルコム, ジャック カラム
    右手と左手のように，物の鏡像体が自身と重ならない構造をもつ時，その物はキラルであるといい，分子やナノ物質でもキラリティは重要な物質の特性である。分子レベル・ナノレベルのキラリティを調べる光学活性分光法を顕微鏡に組み合わせる手法を開発・高度化し，それを用いてナノ物質の局所的なキラリティとその挙動を調べ，応用する研究を行った。局所的なキラリティは従来の光学活性の特性とは異なる挙動を示すことを明らかにした。貴金属ナノ構造と偏光を適切に用いることで，キラリティのない系に分子レベル・ナノレベルのキラリティを誘起する可能性を見出した。
    日本学術振興会, 基盤研究(A), 分子科学研究所, 15H02161
  • 金属ナノ構造に誘起される局所的円偏光電場による磁性体中の磁化制御
    科学研究費助成事業
    2015年04月 - 2017年03月
    岡本 裕巳, 成島 哲也, 西山 嘉男, 橋谷田 俊
    光で物質の磁性を制御する基礎となりうる逆ファラデー効果が，金属ナノ構造物質によって増強するかどうかを検討した。螺旋状の捩れた構造を持つ円偏光を物質に照射すると，その物質に磁化（磁石の性質）が生じる現象（逆ファラデー効果）が知られているが，通常この効果は非常に弱い。金属ナノ構造に光を照射すると，その周辺に通常より強く捩れた円偏光が発生する場合があり，これを利用することで逆ファラデー効果が強く現れ，磁性制御に利用できる可能性があると考え，それを探った。現時点までに円偏光による磁化と思われる信号の検出に成功したので，今後試料や条件を変えた試みを継続し，増強逆ファラデー効果の特性解明を進めたい。
    日本学術振興会, 挑戦的萌芽研究, 分子科学研究所, 15K13683
  • 金ナノ構造体の強い局所光学活性によるキラル光化学反応場の開拓　　　　　　　　　　　　　　　
    科学研究費補助金 特別研究奨励費
    2015年04月 - 2017年03月
    橋谷田 俊
    日本学術振興会, 研究代表者, 競争的資金
  • ナノドット配列における結合励起状態の時空間特性と励起場制御
    科学研究費助成事業
    2010年04月 - 2015年03月
    岡本 裕巳, 成島 哲也, 井村 考平, 西山 嘉男, 小若 泰之, 橋谷田 俊
    本研究では，様々な金属ナノ構造を作成し，その近接場光学イメージの測定と解析を通じて，光電場の時空間構造とそれを決めるプラズモンの相互作用を解明することを第一目的とした。金属微粒子の１次元・２次元配列構造で，増強した光の空間分布の特徴的な構造を見出し，それが微粒子間の相互作用を仮定した簡単なモデルで定性的に解釈できることを示した。金属微粒子の超高速過程等，基礎的な特性に関しても，幾つかの興味深い結果を得た。またナノ空間領域で光学活性による近接場イメージングを可能とし，金属ナノ構造が局所的には極めて強い光学活性を示し，また対称性の高いキラルでないナノ構造でも局所的な光学活性を示すことを見出した。
    日本学術振興会, 基盤研究(S), 分子科学研究所, 22225002

社会貢献活動

  • 差の湯の会
    2013年09月14日 - 2015年11月07日
    出演, 情報提供
    サイエンスカフェ
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