Researcher basic information

• 博士（理学）

• https://researchmap.jp/msakoda?lang=en

• https://jglobal.jst.go.jp/detail?JGLOBAL_ID=201801019943096547
• https://www.eng.hokudai.ac.jp/labo/topology/topo/index.html

• 201801019943096547

• サイズ効果
• 遷移金属酸化物
• 強相関化合物
• Molecular beam epitaxy
• High-Tc superconductor

• Nanotechnology/Materials, Thin film/surface and interfacial physical properties
• Natural Science, Magnetism, superconductivity and strongly correlated systems

• Bachelor's degree program, School of Engineering
• Master's degree program, Graduate School of Engineering
• Doctoral (PhD) degree program, Graduate School of Engineering

Research activity information

• Mar. 2025, 公益財団法人熊谷科学技術振興財団, 熊谷研究助成表彰

• Bose glass in Ca2RuO4 nanofilms
  Hiroyoshi Nobukane; Koki Hirose; Kakeru Isono; Mizuki Higashiizumi; Masahito Sakoda; Korekiyo Takahashi; Satoshi Tanda
  Communications Materials, Springer Science and Business Media LLC, 10 Aug. 2026
  Scientific journal, Abstract
  
  Weak localization of bosons can give rise to an exotic quantum state known as a Bose glass, characterized by the absence of global phase coherence yet finite conductivity. Here, we report signatures of a Bose glass state in the weak localization regime of the ruthenium oxide Ca ₂ RuO ₄ nanofilms. The electrical resistivity exhibits a characteristic logarithmic temperature dependence, ρ  ~ ln(1/ T ), consistent with bosonic weak localization. Furthermore, β -function scaling analysis reveals a distinct “vertical flow,” indicating a qualitative change in scaling behavior associated with localized bosonic transport. These results suggest that signatures of Cooper pairs persist up to high temperatures of  ~ 220 K. We identify two quantum critical points associated with changes in scaling behavior between the Bose glass and superconducting regimes, and between the Bose glass and strongly localized regimes. We demonstrate that the ground state is governed by the strength of localization arising from the interplay of electron correlation, lattice distortion of the RuO ₆ octahedra, and reduced dimensionality, where film thickness acts as an effective control parameter. These findings establish Ca ₂ RuO ₄ nanofilms as a platform for exploring bosonic localization in strongly correlated oxides, with implications for cuprates and nickelates.
• Mott insulators appearing at a thickness period corresponding to nesting in CaRuO3
  M. Sakoda; H. Nobukane; S. Shimoda; K. Ichimura
  Applied Physics Letters, 126, 183101, May 2025, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Bose glass and Fermi glass
  Korekiyo Takahashi; Keiji Nakatsugawa; Masahito Sakoda; Yoshiko Nanao; Hiroyoshi Nobukane; Hideaki Obuse; Satoshi Tanda
  Scientific Reports, 13, 1, 12434, Springer Science and Business Media LLC, 01 Aug. 2023, [Peer-reviewed]
  Scientific journal, Abstract
  
  It is known that two-dimensional superconducting materials undergo a quantum phase transition from a localized state to superconductivity. When the disordered samples are cooled, bosons (Cooper pairs) are generated from Fermi glass and reach superconductivity through Bose glass. However, there has been no universal expression representing the transition from Fermi glass to Bose glass. Here, we discovered an experimental renormalization group flow from Fermi glass to Bose glass in terms of simple $$\beta$$-function analysis. To discuss the universality of this flow, we analyzed manifestly different systems, namely a Nd-based two-dimensional layered perovskite and an ultrathin Pb film. We find that all our experimental data for Fermi glass fall beautifully into the conventional self-consistent $$\beta$$-function. Surprisingly, however, flows perpendicular to the conventional $$\beta$$-function are observed in the weakly localized regime of both systems, where localization becomes even weaker. Consequently, we propose a universal transition from Bose glass to Fermi glass with the new two-dimensional critical sheet resistance close to $$R_\Box = h/e^{2}$$.
• Transition from Metal to Mott Insulator Controlled by Growth Conditions on CaRuO₃ Ultrathin Films
  Masahito Sakoda; Kazushi Shinya
  Journal of the Physical Society of Japan, 92, 6, 064601, Physical Society of Japan, 15 Jun. 2023, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Enhancement of Extraordinary Size Effect on CaRuO₃ Ultrathin Films
  M. Sakoda; M. Kouda; K. Shinya; S. Shimoda
  Advanced Electronic Materials, 9, 2201312, 20 Apr. 2023, [Peer-reviewed], [Lead author, Corresponding author]
  Scientific journal
• Periodic Metal–Insulator Transitions Induced by the Quantization of Film Thickness at the Fermi Wavelength
  迫田將仁; 延兼啓純; 丹田聡
  固体物理（アグネ技術センター）, 57, 10, 23, 32, Oct. 2022, [Invited], [Lead author, Corresponding author]
• Extraordinary alternating metal-insulator transitions in CaRuO₃ ultrathin films at integer multiples of 25 Å of thickness
  M. Sakoda; H. Nobukane; S. Shimoda; S. Tanda
  Physical Review B, 17 Nov. 2021, [Peer-reviewed], [Lead author, Corresponding author]
  English, Scientific journal
• Author Correction: Visualization of the strain-induced topological phase transition in a quasi-one-dimensional superconductor TaSe₃
  Chun Lin; Masayuki Ochi; Ryo Noguchi; Kenta Kuroda; Masahito Sakoda; Atsushi Nomura; Masakatsu Tsubota; Peng Zhang; Cedric Bareille; Kifu Kurokawa; Yosuke Arai; Kaishu Kawaguchi; Hiroaki Tanaka; Koichiro Yaji; Ayumi Harasawa; Makoto Hashimoto; Donghui Lu; Shik Shin; Ryotaro Arita; Satoshi Tanda; Takeshi Kondo
  Nature Materials, 20, 8, 1168, 1168, Springer Science and Business Media {LLC}, Aug. 2021
  Scientific journal
• Visualization of the strain-induced topological phase transition in a quasi-one-dimensional superconductor TaSe₃
  Chun Lin; Masayuki Ochi; Ryo Noguchi; Kenta Kuroda; Masahito Sakoda; Atsushi Nomura; Masakatsu Tsubota; Peng Zhang; Cedric Bareille; Kifu Kurokawa; Yosuke Arai; Kaishu Kawaguchi; Hiroaki Tanaka; Koichiro Yaji; Ayumi Harasawa; Makoto Hashimoto; Donghui Lu; Shik Shin; Ryotaro Arita; Satoshi Tanda; Takeshi Kondo
  Nature Materials, 20, 8, 1093, 1099, Springer Science and Business Media {LLC}, Aug. 2021, [Peer-reviewed]
  Scientific journal
• 2020-11-15
  Kubo Tomoya; Sakoda Masahito; Matsuoka Eiichi; Terashima Taichi; Kikugawa Naoki; Uji Shinya; Sugawara Hitoshi
  Journal of the Physical Society of Japan, 89, 11, 114704, 114704, Physical Society of Japan, 15 Nov. 2020, [Peer-reviewed]
  English, Scientific journal
• Universal scaling behavior of the upper critical field in strained FeSe_0.7Te_0.3 thin films
  Feifei Yuan; Vadim Grinenko; Kazumasa Iida; Stefan Richter; Aurimas Pukenas; Werner Skrotzki; Masahito Sakoda; Michio Naito; Alberto Sala; Marina Putti; Aichi Yamashita; Yoshihiko Takano; Zhixiang Shi; Kornelius Nielsch; Ruben Hühne
  New Journal of Physics, 20, 9, 093012, 093012, {IOP} Publishing, 01 Sep. 2018, [Peer-reviewed]
  Scientific journal
• Recent progress in thin-film growth of Fe-based superconductors: superior superconductivity achieved by thin films
  M. Sakoda; K. Iida; M. Naito
  Supercond. Sci. Tech., 31, 9, 093001, 093001, {IOP} Publishing, Jul. 2018, [Peer-reviewed], [Invited], [Lead author]
  English, Scientific journal
• Past 10 Years and Recent Progress in the Thin-film Growth of Fe-based Superconductors
  SAKODA Masahito; NAITO Michio
  TEION KOGAKU (Journal of Cryogenics and Superconductivity Society of Japan), 52, 6, 422, 432, CRYOGENICS AND SUPERCONDUCTIVITY SOCIETY OF JAPAN, Nov. 2017, [Peer-reviewed], [Invited], [Lead author, Corresponding author]
  Japanese, Scientific journal,

  This article reviews the developments over the past 10 years in the thin film growth of Fe-based superconductors, including recent topics of interest in this field. At the beginning of the research, there was pessimism that thin films of the highest-T_c compound, LnFeAs(O,F), would not be easy to grow since it is composed of five elements, namely two cations and three anions. The situation is different from cuprates such as Bi₂Sr₂CaCuO₈, which also consists of five elements, but four cations and one anion. Indeed, there were enormous struggles in the initial attempts to grow LnFeAs(O,F) using pulsed laser deposition. But a major breakthrough was achieved using molecular beam epitaxy, and now LnFeAs(O,F) films with T_c^end over 55 K are routinely grown, at least in Japan. The current best films of many of Fe-based superconductors show superconducting properties substantially superior to those of bulk single crystals. Furthermore the simplest material among Fe-based superconductors, FeSe, whose bulk T_c is as low as 8 K, is opening up a new frontier. The T_c of ultra-thin FeSe films are as high as 40 K or possibly it may even reach >100 K in the form of single atomic-layer films.

• Molecular beam epitaxy growth of SmFeAs(O,F) films with T_c=55 K using the new fluorine source FeF₃
  Masahito Sakoda; Akihiro Ishii; Kenji Takinaka; Michio Naito
  JOURNAL OF APPLIED PHYSICS, 122, 1, 015306, 015306, Jul. 2017, [Peer-reviewed], [Lead author, Corresponding author]
  English, Scientific journal
• The influence of the in-plane lattice constant on the superconducting transition temperature of FeSe_0.7Te_0.3 thin films
  Feifei Yuan; Kazumasa Iida; Vadim Grinenko; Paul Chekhonin; Aurimas Pukenas; Werner Skrotzki; Masahito Sakoda; Michio Naito; Alberto Sala; Marina Putti; Aichi Yamashita; Yoshihiko Takano; Zhixiang Shi; Kornelius Nielsch; Ruben Huehne
  AIP ADVANCES, 7, 6, 065015, 065015, Jun. 2017, [Peer-reviewed]
  English, Scientific journal
• Superconducting tunnel junctions on MgB₂ using MgO and CaF₂ as a barrier
  Masahito Sakoda; Masato Aibara; Kazuya Mede; Motoyuki Kikuchi; Michio Naito
  PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, 530, 82, 86, Nov. 2016, [Peer-reviewed], [Invited], [Lead author, Corresponding author]
  English, Scientific journal
• One-step growth of SmFeAs(O,F) films by molecular beam epitaxy using FeF₂ as a fluorine source
  H. Sugawara; T. Tsuneki; D. Watanabe; A. Yamamoto; M. Sakoda; M. Naito
  SUPERCONDUCTOR SCIENCE & TECHNOLOGY, 28, 1, 015005, 015005, Jan. 2015, [Peer-reviewed]
  English, Scientific journal
• De Haas-van Alphen effect in RTi₂Al₂₀ (R = La, Pr, and Sm)
  S. Nagashima; T. Nishiwaki; A. Otani; M. Sakoda; E. Matsuoka; H. Harima; H. Sugawara
  JPS Conf. Proc., 3, 011019, 2014, [Peer-reviewed]
  English, International conference proceedings
• Shubnikov-de Haas effect in CeRu₂Al₁₀
  M. Sakoda; T. Nishiwaki; E. Matsuoka; H. Harima; H. Tanida; M. Sera; H. Sugawara
  JPS Conf. Proc., 3, 011043, 2014, [Peer-reviewed], [Lead author]
  English, International conference proceedings
• Single Crystal Growth and Transport Properties of RRu₂Al₁₀ (R=La and Pr)
  Masahito Sakoda; Kazuhiro Kubota; Shuhei Tanaka; Eiichi Matsuoka; Hitoshi Sugawara; Tatsuma D. Matsuda; Yoshinori Haga
  Journal of the Physical Society of Japan, 81, SB011, Dec. 2012, [Peer-reviewed], [Lead author]
  English, Scientific journal
• High Field Magnetoresistance and de Haas-van Alphen Effect in LaRu₂Al₁₀
  Masahito Sakoda; Shuhei Tanaka; Eiichi Matsuoka; Hitoshi Sugawara; Hisatomo Harima; Fuminori Honda; Rikio Settai; Yoshichika Onuki; Tatsuma D. Matsuda; Yoshinori Haga
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 80, 8, 084716, 084716, Aug. 2011, [Peer-reviewed], [Lead author]
  English, Scientific journal
• First-order-like antiferromagnetic transition in rare-earth palladium bronze SmPd3S4
  E. Matsuoka; M. Watahiki; M. Sakoda; H. Sugawara; T. Sakurai; H. Ohta; H. Onodera
  Journal of Physics: Conference Series, 273, 012138, 2011, [Peer-reviewed]
  English, International conference proceedings
• de Haas-van Alphen effect in SmOs4P12
  S. Tanaka; M. Sakoda; E. Matsuoka; H. Sugawara; R. Settai; Y. Onuki
  Journal of Physics: Conference Series, 273, 012060, 2011, [Peer-reviewed]
  English, International conference proceedings

• Mott size effect
  迫田將仁; 延兼啓純; 小浦姿; 下田周平; 市村晃一, 日本物理学会講演概要集(CD-ROM), 79, 2, 2024
• Bose glass in ruthenates
  廣瀬耕大; 延兼啓純; 磯野翔; 東泉瑞希; 迫田將仁; 高橋是清; 丹田聡; 丹田聡, 日本物理学会講演概要集(CD-ROM), 79, 2, 2024
• 走査電子顕微鏡の照射電流計開発
  下田周平; 女池竜二; 迫田將仁; 丹田聡; 延兼啓純, 機器・分析技術研究会(CD-ROM), 2023, 2023
• Discovery of Metal-Insulator Transition at 25 Å Periodic Thickness
  迫田將仁; 延兼啓純; 下田周平; 丹田聡, 応用物理学会春季学術講演会講演予稿集(CD-ROM), 69th, 2022
• Ferromagnetic phase emerged by controlling oxygen content in Ca₂RuO₄ nanocrystals
  棚橋慧太; 能村貴宏; 延兼啓純; 迫田將仁; 丹田聡, 応用物理学会春季学術講演会講演予稿集(CD-ROM), 67th, 2020
• Modulation of lattice and magnetism by nanocrystallization of Ca₂RuO₄
  棚橋慧太; 延兼啓純; 迫田將仁; 丹田聡; 能村貴宏, 応用物理学会秋季学術講演会講演予稿集(CD-ROM), 81st, 2020
• Ca₂RuO₄の粒径と構造転移の関係性
  棚橋慧太; 能村貴宏; 延兼啓純; 迫田將仁; 丹田聡; 秋山友宏, 応用物理学会秋季学術講演会講演予稿集(CD-ROM), 80th, 2019
• 分子線エピタキシー法(MBE)を用いた鉄系超伝導体SmFeAs(O,F)薄膜の1-Step成長(2)
  常木孝信; 渡辺大樹; 迫田將仁; 山本明保; 内藤方夫, 応用物理学会秋季学術講演会講演予稿集(CD-ROM), 75th, 2014
• de Haas-van Alphen effect in RTi_2Al_<20>(R=La,Pr,Sm)
  Nagashima S.; Nishiwaki T.; Ohtani A.; Sakoda M.; Matsuoka E.; Harima H.; Sugawara H., Meeting abstracts of the Physical Society of Japan, 68, 2, 456, 456, 26 Aug. 2013
  The Physical Society of Japan (JPS), Japanese
• 26pXT-7 The Fermi surface in RT_2Al_<10> (R=rare earth, T=transition metal)
  Sakoda M.; Ohtani A.; Nagashima S.; Nishiwaki T.; Kubota K.; Matsuoka E.; Sugawara H.; Harima M.; Harima H., Meeting abstracts of the Physical Society of Japan, 68, 1, 585, 585, 26 Mar. 2013
  The Physical Society of Japan (JPS), Japanese
• 26pEC-14 Fundamental Physical Properties in RT_2Al_<10>(R=La,Pr,T=Fe,Ru,Os)
  Sakoda M; Tanaka S; Matsuoka E; Sugawara H; Sakurai T; Ohta H; Matsuda T.D; Haga Y, Meeting abstracts of the Physical Society of Japan, 66, 1, 03 Mar. 2011
  The Physical Society of Japan (JPS), Japanese
• 26pWJ-5 Electrical and Magnetic Properties in RRu_2Al_<10>(R=La,Pr)
  迫田 將仁; 田中 修平; 松岡 英一; 菅原 仁; 播磨 尚朝; 櫻井 敬博; 太田 仁; 本多 史憲; 摂待 力生; 大貫 惇睦; 松田 達磨; 芳賀 芳範, Meeting abstracts of the Physical Society of Japan, 65, 2, 18 Aug. 2010
  The Physical Society of Japan (JPS), Japanese

• Enhancement of Extraordinary size effect
  M. Sakoda
  International Congress on Pure & Applied Chemistry Bali (ICPAC Bali) 2023, 14 Sep. 2023, Invited oral presentation
  [Invited]
• Extraordinary Metal-insulator Transitions at 25 Å Periodic Thickness
  M. Sakoda
  International Congress on Pure & Applied Chemistry Kota Kinabalu (ICPAC KK) 2022, 23 Nov. 2022, Invited oral presentation
  [Invited]
• Fabrication method of superconducting junctions on MgB2 and SmFeAs(O,F)
  M. Sakoda; M. Naito
  International Congress on Pure & Applied Chemistry Langkawi (ICPAC Langkawi) 2018, Nov. 2018, English, Invited oral presentation
  [Invited], [International presentation]
• Fabrication of single crystal thin films and tunneling junctions using MgB2 and Iron-based superconductor SmFeAs(O,F)
  M. Sakoda; M. Kikuchi; M. Naito
  International Congress on Pure & Applied Chemistry (ICPAC) 2018, Mar. 2018, English, Keynote oral presentation
  [Invited], [International presentation]
• Fabrication of thin films and tunneling junctions using MgB2 and iron-based superconductor SmFeAs(O,F)
  M. Sakoda; M. Kikuchi; M. Naito
  The 15th International Conference on Advanced Materials (IUMRS-ICAM 2017), Aug. 2017, English, Invited oral presentation
  [Invited], [International presentation]
• Fabrication of thin films and junctions on high-Tc superconductors using molecular beam epitaxy
  M. Sakoda; M. Kikuchi; M. Naito
  International Symposium on Pure & Applied Chemistry (ISPAC) 2017, Jun. 2017, English, Invited oral presentation
  [Invited], [International presentation]
• Fabrication of thin films and Josephson junctions on MgB2 and SmFeAs(O,F) using molecular beam epitaxy
  M. Sakoda; M. Kikuchi; A. Ishii; M. Naito
  International Symposium on Pure & Applied Chemistry (ISPAC) 2016, Aug. 2016, English, Invited oral presentation
  [Invited], [International presentation]
• SIS and SIN junctions of MgB2 using CaF2, AlOx, and MgO as the barriers
  M. Sakoda; K. Mede; M. Naito
  The 8th East Asia Symposium on Superconductor Electronics, Nov. 2015, English, Invited oral presentation
  [Invited], [International presentation]
• 1-step growth of SmFeAs(O,F) films using various fluorine sources by molecular beam epitaxy
  M. Sakoda; A. Ishii; T. Tsuneki; M. Naito
  28th International Symposium on Superconductivity, Nov. 2015, English, Invited oral presentation
  [Invited], [International presentation]

• 応用物理学実験Ⅰ, 2024年, 学士課程, 工学部
• 応用物理学実験Ⅱ, 2024年, 学士課程, 工学部

• Feb. 2014 - Present
  THE JAPAN SOCIETY OF APPLIED PHYSICS
• Aug. 2010 - Present
  THE PHYSICAL SOCIETY OF JAPAN

• 量子臨界スイッチングの創出：Mott絶縁相に自在に出し入れ可能な電界デバイス
  科学研究費助成事業
  Apr. 2025 - Mar. 2028
  迫田 將仁
  日本学術振興会, 基盤研究(C), 北海道大学, Principal investigator, 25K08466
• Enhancing the superconducting critical temperature by single layer films
  Grants-in-Aid for Scientific Research
  01 Apr. 2016 - 31 Mar. 2018
  Naito Michio
  The superconductivity in Fe(Se,Te) was reported just after superconducting FeAs compounds were discovered by the Hosono group in 2008. At the beginning, the Tc of Fe(Se,Te) may not go over 15 K, but it was reported in 2012 by the Chinese groups that the Tc of monolayer FeSe films on SrTiO3 substrates may reach 77 K. Furthermore, very recently (during the period of this Kakenhi research), it was announced by several groups including Japanese groups that Tc as high as 40 K can be reached in FeSe ultrathin films given carrier injection and/or electrochemical etching by an EDLT (Electric Dipole Layer Transistor). Therefore such experiments have also been performed in our research. As a result, we achieved Tc ~ 50 K in FeSe films consisting of several molecular layers on Al2O3 substrates, which demonstrate that a SrTiO3 substrate is not prerequisite to achieve high-Tc in FeSe films.
  Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Exploratory Research, Tokyo University of Agriculture and Technology, 16K13832
• Study of Undergraduate Laboratory Subjects without Manuals
  Grants-in-Aid for Scientific Research
  01 Apr. 2014 - 31 Mar. 2018
  Matsuzaki Seiji
  Nowadays, educational effects of active learning are said to be superior than those of passive methods. Is active learning also effective in undergraduate laboratory in higher education? Our group introduced some subjects into undergraduate laboratory courses without detailed manuals. We measured their educational effects from some questionnaires, systematic evaluation of the procedure of students’ thinkings, and results of students’ presentations. In conclusion, their effects were superior than cooking-recipe type experiments in understanding physical concepts, and they made students more motivated.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Tokyo University of Agriculture and Technology, 26350187

• International Grant Reviewer, Croatian Science Foundation (HRZZ)
  2026
  Peer review
  Croatian Science Foundation, HRZZ
• Review activity for Journal of Magnetism and Magnetic Materials
  2025
  Peer review
  Elsevier
• Review activity for Nature communications
  2024
  Peer review
  Nature Publishing Group
• Review activity for Nature communications
  2024
  Peer review
  Nature Publishing Group

• リフレッシュ理科教室
  18 Oct. 2025
  Lecturer
  応用物理学会北海道支部
• リフレッシュ理科教室
  19 Oct. 2024
  Lecturer
  応用物理学会北海道支部
• オープンキャンパス
  2019
  Lecturer
  北海道大学・工学部
• オープンキャンパス
  2014
  Lecturer
  東京農工大学・工学部

• 薄膜の電気抵抗が厚さに依存して周期的に振動する現象を発見
  01 Jan. 2022
  科学新聞社
  [Paper]

• Feb. 2017
  高圧ガス製造保安責任者免状（乙種機械）
• Sep. 2014
  危険物取扱者免状（甲種）