KOSAKA Hideo

Affiliation

Faculty of Engineering, Division of Intelligent Systems Engineering

Job Title

Professor

Research Fields, Keywords

quantum information physics, 光子, 電子スピン, 量子テレポーテーション, 量子中継, 量子転写


ORCID  https://orcid.org/0000-0002-3778-7236

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Education 【 display / non-display 】

  • 　
    -
    1999.9

    Kyoto University   Doctor Course   Completed

  • 1987.4
    -
    1989.3

    Kyoto University   Master Course   Completed

  • 1983.4
    -
    1987.3

    Kyoto University   Graduated

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Degree 【 display / non-display 】

  • Doctor of Engineering - Kyoto University

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Campus Career 【 display / non-display 】

  • 2014.4
    　
    　

    Duty   Yokohama National UniversityFaculty of Engineering   Division of Intelligent Systems Engineering   Professor  

  • 2020.10
    　
    　

    Concurrently   Yokohama National UniversityInstitute of Advanced Sciences   Professor  

  • 2018.4
    　
    　

    Concurrently   Yokohama National UniversityGraduate school of Engineering Science   Department of Mathematics, Physics, Electrical Engineering and Computer Science   Professor  

  • 2014.4
    　
    　

    Concurrently   Yokohama National UniversityCollege of Engineering Science   Department of Mathematics, Physics, Electrical Engineering and Computer Science   Professor  

  • 2014.4
    　
    　

    Concurrently   Yokohama National UniversityGraduate School of Engineering   Department o Physics, Electrical and Computer Engineering   Professor  

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External Career 【 display / non-display 】

  • 2003.7
    -
    2014.3

     

  • 1989.4
    -
    2003.6

     

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Academic Society Affiliations 【 display / non-display 】

  • 2000
    　
    　
     

    日本物理学会

  • 2000
    　
    　
     

    応用物理学会

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Research Areas 【 display / non-display 】

  • Natural Science / Semiconductors, optical and atomic physics

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Research Career 【 display / non-display 】

  • 量子もつれ中継技術の研究開発／遠隔ノード間での量子もつれ純粋化技術／ハイブリッド量子中継器へ向けた研究開発

    Project Year：

  • 量子ドットにおける単一光子から単一電子スピンへの量子状態転写

    Project Year：

  • 量子もつれ中継技術の研究開発／超伝導技術に基づく多ビット量子もつれ制御と光インターフェース技術／量子中継ノードにおける量子演算回路と量子トランスデューサの研究開発

    Project Year：

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Books 【 display / non-display 】

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Thesis for a degree 【 display / non-display 】

  • 面発光機能素子の開発とその応用に関する研究

    小坂　英男

    1999.9

    Doctoral Thesis   Single Work  

    DOI

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    京都大学　大学院　工学研究科　電子物性工学専攻
    コンピュータのネットワーク化、並列処理化に伴い、データ伝送の大容量化が望まれている。垂直共振器型面発光レーザ（ＶＣＳＥＬ）は面に垂直方向に発光するため、現状の端面発光レーザに対して二次元集積性に優れ、大容量データの並列伝送を可能とする技術として期待されている。本研究ではＶＣＳＥＬの利点を生かして実用化するために駆動電圧上昇の問題をメサ光閉じ込め構造の導入により克服し、光情報処理に必要な発光、受光、スイッチ、メモリ、光増幅機能を集積一体化した面発光機能素子を実現した。また、並列データ伝送への応用を目指した２次元ＶＣＳＥＬ伝送モジュールとその並列性を生かしたＶＣＳＥＬ光スイッチの開発を行った。

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Papers 【 display / non-display 】

  • Spatially Resolved Optical Responses of a Superconducting Nanowire Microwave Resonator

    Hirotsuru Rento, Kurokawa Hodaka, Takaki Kazuyo, Terai Hirotaka, Kosaka Hideo

    Physical Review Letters   136 ( 8 )   86901   2026.2  [Reviewed]

    CiNii Research

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society   Joint Work  

    Understanding the optical response of a superconducting microwave resonator is crucial for applications ranging from single-photon detection to quantum transduction between the microwave and optical domains. This topic is gaining significant attention for scaling up quantum computers. However, interactions between the pump light and superconducting resonators often induce unintended resonance frequency shifts and linewidth broadening. In this study, we measure the local optical response of a NbTiN nanowire resonator using a laser-scanning microwave spectroscopy system integrated with a dilution refrigerator. The optical response of the resonator correlates with the resonance modes and position, which we attribute to interactions between two-level systems (TLSs) and laser-induced phonons. These findings establish the TLS-phonon interactions as the dominant mechanism underlying laser-induced resonance variations, providing critical insights for the design and optimization of quantum transducers and superconducting single-photon detectors.

  • Quantum teleportation of a photon via absorption and emission for quantum repeater nodes

    Reyes Raustin, Sekiguchi Yuhei, Ito Daisuke, Fujiwara Taichi, Watanabe Kansei, Makino Toshiharu, Ka … Show more authors

    npj Quantum Information   12 ( 1 )   1 - 8   2026.1  [Reviewed]

    CiNii Research

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    Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Nature   Joint Work  

    Absorption and emission, fundamental interactions between light and matter, enable the regeneration of a quantum state of light via matter through concatenated quantum state transfer based on the principle of quantum teleportation. This transfer is enabled by electron spin-orbit entanglement and electron-nuclear spin entanglement inherent within the material. Here, we demonstrate that a photon quantum state imprinted in polarization is transferred to another photon emitted from a nitrogen vacancy (NV) center. This transfer is heralded by the result of the Bell state measurement between the electron and nitrogen nuclear spins.Weshow that the minimum number of incident photons needed to achieve transfer is, on average, only 0.1 photons, enabling quantum teleportation over 10 km. This demonstration paves the way for a quantumrepeater that is robust against phase and intensity errors, unlike the conventional photon interference scheme, thereby facilitating practical quantum networks.

  • Spatially resolved optical responses of a superconducting nanowire microwave resonator

    R. Hirotsuru,H. Kurokawa, K. Takaki, H. Terai, H. Kosaka

    Physical Review Letters   2026.2  [Reviewed]

    DOI

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    Language：English   Publishing type：Research paper (scientific journal)   Single Work  

  • The future of quantum technology as seen from the EU, USA and Japan: Experts’ vision over the next two decades

    D Z Anderson, P Chomaz, S Takeuchi,Y Arakawa, Y Baba, O Benson, K Brickman-Soderberg, E Diamanti, D … Show more authors

    Journal of Physics B: Atomic, Molecular and Optical Physics   2026

    DOI

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    Language：English   Publishing type：Research paper (scientific journal)   Single Work  

  • Quantum teleportation of a photon via absorption and emission for quantum repeater nodes

    Raustin Reyes,Yuhei Sekiguchi,Daisuke Ito,Taichi Fujiwara,Kansei Watanabe,Toshiharu Makino,Hiromits … Show more authors

    npj Quantum Information   2025.12  [Reviewed]

    DOI

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    Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Single Work  

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Review Papers 【 display / non-display 】

  • 別冊「量子論のすべて 新訂版」

    Hideo Kosaka、Yuhei Sekiguchi, Hiromitsu Kato, Tokuyuki Teraji,

    Newton   2019.9

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    Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (other)   Joint Work  

  • 量子の世界 第4回 量子テレポーテーション

    科学雑誌 Newton   ( 6月 )   58 - 71   2018.5

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    Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

  • 量子情報の視点でダイヤモンドを眺めると?

    量子情報の視点でダイヤモンドを眺めると?   ( 6 )   2017.11

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    Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Single Work  

  • ダイヤモンドで、次世代量子通信の普及を目指す

    Top Researchers   2017.11

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    Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (other)   Single Work  

    Other Link： http://top-researchers.com/?p=1125

  • 量子暗号通信、その概要と安全性

    小坂 英男

    「SE」（セイフティ エンジニアリング）   44 ( 3 )   188   2017.9

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    Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (bulletin of university, research institution)   Publisher：総合安全工学研究所   Single Work  

    Other Link： http://www.i-s-l.org/shupan/newmokuji_.htm

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Awards 【 display / non-display 】

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Presentations 【 display / non-display 】

  • Quantum repeater node based on emission–absorption processes in an NV center

    H. Kosaka, Y. Sekiguchi, T. Fujiwara, R. Reyes, H. Kato, T. Makino

    WQRN5(The 5th Workshop for Quantum Repeaters and Networks） 

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    Event date： 2026.4

    Language：English   Presentation type：Poster presentation  

  • Quantum Networks at Scale: Insights from Japan

    Hid  [Invited]

    The Quantum Internet Summit  

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    Event date： 2025.12

    Language：English   Presentation type：Oral presentation (invited, special)  

  • ダイヤモンドを使った量子テレポーテーション

    小坂英男  [Invited]

    2025年度 物性セミナーリスト 

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    Event date： 2025.12

    Language：Japanese   Presentation type：Oral presentation (invited, special)  

  • Quantum repeater node based on emission–absorption processes in an NV center

    Yuhei Sekiguchi

    1st ASPIRE ECR Workshop 

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    Event date： 2025.11

    Language：English   Presentation type：Oral presentation (general)  

  • Diamond optomechanical crystal for superconducting-optical hybrid quantum computer

    Hideo Kosaka  [Invited]

    HQSN2025/HQMST2025 

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    Event date： 2025.10

    Language：English   Presentation type：Oral presentation (invited, special)  

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Charge of on-campus class subject 【 display / non-display 】

  • 2026   Quantum Information Physics

    Interfaculty Graduate School of Innovative and Practical Studies

  • 2026   Advanced Quantum Information Physics

    Graduate school of Engineering Science

  • 2026   Quantum Information Physics

    Graduate school of Engineering Science

  • 2026   Electromagnetism 1

    College of Engineering Science

  • 2026   Basics Mechanics Ⅱ

    College of Engineering Science

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Committee Memberships 【 display / non-display 】

  • 公益社団法人 応用物理学会 量子情報工学研究会　

    2022.4  幹事

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    Committee type：Other 

  • 一般社団法人量子技術による新産業創出協議会（Q-STAR）

    2022.4  機関代表

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    Committee type：Other 

  • 一般社団法人量子フォーラム 量子フォーラム・量子鍵配送技術推進委員会委員

    2020.10  推進委員会委員

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    Committee type：Other 

  • 国立研究開発法人 情報通信研究機構 NICT Quantum Camp

    2020.9  実行委員・推進委員・NICT量子人材育成講師

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    Committee type：Other 

  • 量子インターネットタスクフォース　アドバイザリーボード

    2019.5 

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    Committee type：Academic society 

    https://qitf.org/

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Social Contribution(Extension lecture) 【 display / non-display 】

  • NICT Quantum Camp(NQC)　招待講演

    Role(s)： Lecturer

    「量子コンピュータ」「量子通信」の次に来る、「量子中継ネットワーク」  2024.9

  • 科学雑誌Newton「“量子時代”のかぎをにぎる もつれる量子」（2024年10月号）の監修

    Role(s)： Other

    2024.8

  • University of Stuttgart（独）との共同研究契約となる協力覚書（Memorandum of Collaboration, MOC）を締結

    Role(s)： Other

    2024.8

  • 先端科学高等研究院と理化学研究所量子コンピュータ研究センターとの間で連携協定を締結

    Role(s)： Other

    横浜国立大学先端科学高等研究院、理化学研究所  https://www.ynu.ac.jp/hus/koho/32023/detail.html  2024.7

  • 36th International Conference on the Physics of Semiconductors 2024

    Role(s)： Lecturer

    Diamond Spin Qubits for Quantum Communication and Computing  2024.7

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Media Coverage 【 display / non-display 】

  • 量子コンピューター、どう使う？　超伝導・光・シリコン…５方式の開発進む

    朝日新聞  2024.12

  • ノーベル賞でも注目の量子コンピューター　日本の研究者も貢献

    朝日新聞DIGITAL  2024.10

  • 「もつれる量子　離れていても、絡みあう」Newton×朝日新聞

    朝日新聞デジタル  2024.8

  • 横浜国立大学 先端科学高等研究院と理化学研究所 量子コンピュータ研究センターが連携し、量子未来社会実現のための研究を加速

    日経クロステック  2024.7

  • 先端科学高等研究院と理化学研究所 量子コンピュータ研究センターが連携

    横浜国立大学プレスリリース  2024.7

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