Watanabe, Shinichi

写真a

Affiliation

Faculty of Science and Technology, Department of Physics (Yagami)

Position

Professor

E-mail Address

E-mail address

External Links

Career 【 Display / hide

  • 1999.04
    -
    2002.03

    Research Fellow of the Japan Society for the Promotion of Science (DC1)

  • 2002.04
    -
    2004.03

    JSPS Postdoctoral Fellow for Research Abroad

  • 2004.04
    -
    2004.07

    Collaborator Scientific

  • 2004.08
    -
    2007.03

    Assistant Professor (University of Tokyo)

  • 2007.03
    -
    2011.03

    Assistant Professor

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Academic Background 【 Display / hide

  • 1997.03

    The University of Tokyo, Faculty of Science, Department of Physics

    University, Graduated

  • 1999.03

    The University of Tokyo, Graduate School of Science, Physics Department

    Graduate School, Completed, Master's course

  • 2002.03

    The University of Tokyo, Graduate School of Science, Physics Department

    Graduate School, Completed, Doctoral course

Academic Degrees 【 Display / hide

  • Doctor of Science, The University of Tokyo, Coursework, 2002.03

 

Research Areas 【 Display / hide

  • Optical engineering, Photon science (Applied Optics/Quantum Optical Engineering)

  • Condensed matter physics I (Physical Properties I)

Research Keywords 【 Display / hide

  • Terahertz Spectroscopy

  • Semiconductor Nanostructures

  • Organic Conductors

  • Ultrafast Spectroscopy

 

Books 【 Display / hide

  • 基礎高分子科学 第2版

    2020.01

Papers 【 Display / hide

  • Coherent Control of Higher-Order Spin Precession Modes in Ferromagnetic Permalloy Thin Films by Double Pulse Excitation

    Okano M., Takahashi T., Watanabe S.

    Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS (Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS)  2020-May 2020.05

    ISSN  9781943580767

     View Summary

    © 2020 OSA. We demonstrate ultrafast coherent control of higher-order spin precession modes in the permalloy thin film by means of optical techniques. We can selectively excite one of the higher spin precession modes using double pulse excitation.

  • Terahertz time-domain polarimetry (THz-TDP) based on the spinning E-O sampling technique: determination of precision and calibration

    K. Xu, E. Bayati, K. Oguchi, S. Watanabe, D. P. Winebrenner, and M. H. Arbab

    Opt. Express (Optics Express)  28 ( 9 ) 13482 - 13496 2020.04

    Research paper (scientific journal), Joint Work, Accepted

     View Summary

    © 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement We have developed a terahertz time-domain polarimetry (THz-TDP) system by applying frequency modulation to electro-optic sampling detection in a nonlinear crystal. We characterized the precision of this system in determining the polarization angles to be 1.3° for fixed time delay, and 0.5° for complete time-domain waveform. Furthermore, we calculated the Jones matrix of the optical components used for beam propagation to calibrate the induced systematic error. The advantages of employing this calibration approach are demonstrated on a sapphire crystal investigated at different sample test positions in transmission configuration, and using high resistivity Si, AlN and quartz in reflection geometry. The new THz-TDP technique has the advantage of not using any external polarizers, and therefore is not constrained by their optical performance limitations, such as restricted bandwidths and frequency-dependent extinction ratio. Finally, the THz-TDP technique can be easily implemented on existing time-domain spectroscopy (TDS) systems.

  • Ultrafast coherent control of higher-order spin waves in a nife thin film by double-pulse excitation

    M. Okano, T. Takahashi, and S. Watanabe

    Applied Physics Letters (Applied Physics Letters)  117 ( 8 )  2020

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  00036951

     View Summary

    © 2020 Author(s). By using a double-pulse excitation scheme, we demonstrate the optical control of higher-order spin waves in a ferromagnetic permalloy thin film. Three spin precession modes are observed in the film under single pulse excitation. Based on a theoretical calculation, these spin precession modes are assigned to the fundamental Kittel mode and the first- and second-order perpendicular standing spin-wave (PSSW) modes. In order to excite the first-order PSSW mode selectively, we use double-pulse excitation at 400 nm. We show that, by choosing an appropriate time interval between the two pump pulses, it is possible to obtain a relatively large amplitude of the first-order PSSW mode while the amplitudes of the other two modes are almost completely suppressed. By analyzing the spin dynamics, it is found that the spin precession motion under the double-pulse excitation condition can be explained by the interference between the spin waves that have been induced by the first and second pulses. Our finding indicates that the selective excitation of a spin precession mode with a high precession frequency in a ferromagnetic metal may be realized by a multiple-pump pulse excitation scheme with more than two pulses.

  • Evaluation of crystallinity and hydrogen bond formation in stereocomplex poly(lactic acid) films by terahertz time-domain spectroscopy

    J. Hirata, N. Kurokawa, M. Okano, A. Hotta, and S. Watanabe

    Macromolecules (Macromolecules)  53 ( 16 ) 7171 - 7177 2020

    Research paper (scientific journal), Joint Work, Accepted,  ISSN  00249297

     View Summary

    Copyright © 2020 American Chemical Society. Stereocomplex poly(lactic acid) (sc-PLA) crystallites exhibit higher mechanical strength and thermal stability than PLA homocrystallites. In sc-PLA, a hydrogen bond that governs the physical properties is formed between two enantiomeric PLA chains during crystallization. Therefore, the investigation of this hydrogen bond is essential for a better understanding of the properties of sc-PLA. Here, we report on the terahertz spectroscopy of sc-PLA films with low crystallinities. The dielectric function in the terahertz regime allows us to estimate the crystallinity of sc-PLA because various intra- and intermolecular vibration modes lie in the terahertz frequency range. By comparison with X-ray diffraction measurements, the validity of the crystallinity evaluation based on terahertz spectroscopy is verified. Furthermore, a remarkable red-shift of the peak in the imaginary part of the dielectric function occurs as the crystallinity increases. By comparison with Fourier transform infrared spectroscopy, it is considered that this red-shift is caused by the anharmonic nature of the vibrational potential corresponding to the intermolecular libration mode of the sc-PLA crystallites. The hydrogen bond formation associated with the sc-PLA crystallization increases the anharmonicity of the vibrational potential of sc-PLA, and then the red-shift of the peak occurs. Our findings suggest that structural changes due to the stereocomplexation can be sensitively probed by terahertz spectroscopy.

  • Coherent control of higher-order spin precession modes in ferromagnetic permalloy thin films by double pulse excitation

    Okano M., Takahashi T., Watanabe S.

    Optics InfoBase Conference Papers (Optics InfoBase Conference Papers)  Part F182-CLEO-QELS 2020 2020

    ISSN  9781557528209

     View Summary

    CLEO 2020 © OSA 2020. We demonstrate ultrafast coherent control of higher-order spin precession modes in the permalloy thin film by means of optical techniques. We can selectively excite one of the higher spin precession modes using double pulse excitation.

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Papers, etc., Registered in KOARA 【 Display / hide

Reviews, Commentaries, etc. 【 Display / hide

  • テラヘルツセンシングで見えるもの~高分子材料評価への応用~

    渡邉紳一、岡野真人

    一般財団法人電波技術協会 協会報FORN  ( 11 )  2020.11

    Introduction and explanation (commerce magazine), Joint Work

  • テラヘルツ偏光計測による高分子材料の内部異方性検査

    岡野真人, 渡邉紳一

    プラスチックス  ( 10 ) 22 - 25 2019.10

    Introduction and explanation (commerce magazine), Joint Work

  • テラヘルツ分光技術の化学・生命科学への応用

    渡邉紳一

    光学 48 ( 10 ) 396 - 401 2019.10

    Introduction and explanation (scientific journal), Single Work

  • 高分子材料における異方性のテラヘルツセンシング

    渡邉 紳一、岡野 真人、中迫 雅由

    レーザー研究 (一般社団法人レーザー学会)  47 ( 1 ) 21 - 26 2019.02

    Introduction and explanation (scientific journal), Joint Work

  • テラヘルツ偏光分光法を用いた黒色ゴム材料の非破壊検査技術と応用展開

    渡邉 紳一、岡野 真人

    応用物理 (公益社団法人 応用物理学会)  88 ( 2 ) 91 - 95 2019.02

    Introduction and explanation (scientific journal), Joint Work

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Presentations 【 Display / hide

  • 複素誘電率スペクトル解析によるポリ乳酸薄膜の熱誘起状態変化の観測

    岡野真人, 中村円香, 渡邉紳一

    テラヘルツ科学の最先端VII, 2020.11, Oral Presentation(general)

  • 非同期サンプリング法によるテラヘルツ偏光分光測定装置の開発

    中川真由莉, 岡野真人, 渡邉紳一

    テラヘルツ科学の最先端VII, 2020.11, Oral Presentation(general)

  • テラヘルツ偏光計測によるゴム伸縮過程における内部カーボンナノフィラー構造変化の推定

    水田圭祐, 岡野真人, 森本崇宏, 阿多誠介, 渡邉紳一

    日本物理学会2020年秋季大会, 2020.09, Poster (general)

  • ダブル光パルス励起による金属強磁性薄膜中の高次スピン波モードの制御

    岡野真人, 高橋知宏, 渡邉紳一

    Spin-RNJ 若手オンライン研究発表会, 2020.06, Oral Presentation(general)

  • Coherent control of higher-order spin precession modes in ferromagnetic permalloy thin films by double pulse excitation

    M. Okano, T. Takahashi, and S. Watanabe

    CLEO 2020, 2020.05, Oral Presentation(general)

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • 高分子破壊現象プローブのための動的テラヘルツ劣化観察装置の開発

    2018.04
    -
    2021.03

    Grant-in-Aid for Scientific Research, Research grant, Principal Investigator

  • テラヘルツ偏光イメージング分析技術の成果事業化検証のための装置開発

    2017.10
    -
    2018.03

    科学技術振興機構, 大学発新産業創出プログラム 社会還元加速プログラム(SCORE), Commissioned research, Principal Investigator

  • 偏光コム分光法の創出

    2016.04
    -
    2018.03

    Grant-in-Aid for Scientific Research, 渡邉紳一, Principal Investigator

  • 高速・高精度テラヘルツ時間領域分光ポーラリメータの開発と産業応用展開

    2014.09
    -
    2019.03

    科学技術振興機構, 産学共創基礎基盤研究プログラム, Commissioned research, Principal Investigator

  • 高速・高精度テラヘルツ偏光スペクトル計測を用いた非破壊・非接触イメージング技術の研究開発

    2014.08
    -
    2015.03

    総務省, 戦略的情報通信研究開発推進事業, Commissioned research

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Works 【 Display / hide

  • テラヘルツ光で見るゴム深部のひずみ ─光でミクロの構造に迫る─

    渡邉紳一

    JSTニュース2017年9月号, 

    2017.09
    -
    Present

    Other, Single

  • 日経産業新聞 朝刊8面

    2017.01
    -
    Present

    Other, Joint

  • 化学工業日報 朝刊8面

    WATANABE SHINICHI

    2012.07
    -
    Present

    Other

  • 日経産業新聞 朝刊11面

    WATANABE SHINICHI

    2012.07
    -
    Present

    Other

  • 日刊工業新聞 朝刊17面

    WATANABE SHINICHI

    2012.07
    -
    Present

    Other

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Intellectual Property Rights, etc. 【 Display / hide

  • 光学測定装置、光学測定方法、及び応力検査方法

    Application No.: PCT/JP2017/030814  2017.08 

    Patent, Joint, PCT international application

  • 光学測定装置、光学測定方法、及び応力検査方法

    Application No.: 特願2016-167370  2016.08 

    Patent, Joint, National application

  • デュアルコム分光法を用いた偏光計測装置及び偏光計測方法

    Application No.: 特願2016-017537  2016.02 

    Patent, Joint

  • 偏波解析装置、及び偏波解析方法

    Application No.: 特願2015-124617  2015.06 

    Patent, Joint

Awards 【 Display / hide

  • IAAM Scientist Medal

    Shinichi Watanabe, 2018.05, International Association of Advanced Materials, Terahertz polarization spectroscopy as a novel tool for nondestructive internal strain sensing of rubber and polymeric materials

    Country: Sweden

     View Description

    New Age Technology and Innovations 分野における著しく優れた研究による

  • 第42回(2017年春季)応用物理学会講演奨励賞受賞

    森脇淳仁、岡野真人、渡邉紳一, 2017.09, 応用物理学会, テラヘルツ偏光計測による黒色ゴム材料の内部歪みイメージング

  • Best Student Papers

    K. Sumihara, S. Okubo, M. Okano, H. Inaba, and S. Watanabe, 2017.03, Optical Society of America, Development of Precise Polarization Measurement System Using Dual-comb Spectroscopy

  • The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology, The Young Scientists’ Prize

    Shinichi Watanabe, 2014.04, Ministry of Education, Culture, Sports, Science and Technology, テラヘルツ新分光技術の開拓と物質科学応用に関する研究

  • Young Scientist Award of the Physical Society of Japan

    WATANABE SHINICHI, 2012.03, The Physical Society of Japan, Experimental studies on non-equilibrium carrier dynamics in low-dimensional organic materials by time-resolved terahertz spectroscopy

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Courses Taught 【 Display / hide

  • SOLID STATE PHYSICS 3

    2020

  • SOLID STATE PHYSICS 1

    2020

  • PHYSICS SEMINAR 1

    2020

  • PHYSICS LABORATORIES 2

    2020

  • PHYSICS LABORATORIES 1

    2020

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Courses Previously Taught 【 Display / hide

  • 物性物理学第1

    Keio University, 2020, Autumn Semester, Major subject, Lecture

  • 物性物理学第3

    Keio University, 2020, Autumn Semester, Major subject, Lecture, Lecturer outside of Keio

  • 物理学実験I,II

    Keio University, 2020, Full academic year, Major subject, Laboratory work/practical work/exercise

  • 論文講読発表

    慶應義塾大学, 2020, Major subject

  • 自然科学実験

    Keio University, 2020, Spring Semester, General education subject, Laboratory work/practical work/exercise

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Social Activities 【 Display / hide

  • 東京大学理学系COE合同若手シンポジウム実行委員会

    2006.02
    -
    2006.07

     View Summary

    物理学専攻教員代表

  • 第10回関東光科学若手研究会企画・運営

    2015.04
    -
    2015.10

Memberships in Academic Societies 【 Display / hide

  • テラヘルツテクノロジーフォーラム委員会,研究交流委員会,基礎部門, 

    2010.06
    -
    Present
  • 日本物理学会, 

    1997.06
    -
    Present
  • 応用物理学会, 

    2007.01
    -
    Present
  • 高分子学会, 

    2015.10
    -
    Present
  • The Optical Society (OSA), 

    2013.01
    -
    Present

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Committee Experiences 【 Display / hide

  • 2018.05
    -
    Present

    総務委員会委員長(理事), テラヘルツテクノロジーフォーラム

  • 2015.04
    -
    2018.05

    総務委員会委員, テラヘルツテクノロジーフォーラム

  • 2015.04
    -
    2017.03

    機関誌編集委員, 応用物理学会

  • 2012.04
    -
    2014.03

    新著紹介小委員会委員, 一般社団法人日本物理学会

  • 2010.06
    -
    Present

    委員, テラヘルツテクノロジーフォーラム委員会,研究交流委員会,基礎部門

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