Itoh, Kohei

写真a

Affiliation

President and Vice-Presidents （Mita）

Position

President

Related Websites

External Links
Page Top ▲

Career 【 Display / hide 】

  • 1995.01
    -
    1995.03

    米国Lawrence Berkeley国立研究所 ,客員研究員

  • 1995.04
    -
    1998.03

    慶應義塾大学（理工学部） ,助手

  • 1998.04
    -
    2002.03

    慶應義塾大学（理工学部）,専任講師

  • 1998.10
    -
    2001.09

    科学技術振興事業団さきがけ研究21,研究員（兼任）

  • 2000.04
    -
    2001.03

    名古屋大学 ,非常勤講師（兼任）

display all >>

Page Top ▲

Academic Background 【 Display / hide 】

  • 1989.03

    Keio University, Faculty of Science and Engineering, 計測工学科

    University, Graduated

  • 1992.12

    University of California, Berkeley, Materials Science

    United States, Graduate School, Completed, Master's course

  • 1994.12

    University of Calfifornia, Berkeley, Materials Science

    United States, Graduate School, Completed, Doctoral course

Page Top ▲

Academic Degrees 【 Display / hide 】

  • 　, Other, 1994.12

Page Top ▲
 

Books 【 Display / hide 】

  • Defects for Quantum Information Processing in Silicon

    E, Abe and K. M. Itoh, Woodhead Publishing, 2018.06,  Page： 306

    Scope: Capter 9 of “Defects in Advanced Electronic Materials and Novel Low Dimensional Structures,”

  • ダイヤモンド電子スピン量子センサー

    伊藤公平, 丸善出版, 2017.11

    Scope: 「カーボンが創る未来社会　一種類の元素の様々な構造に支えられて」第2-5章

  • Silicon Quantum Information Processing

    T. Sekiguchi and K. M. Itoh, Springer, 2015.12

    Scope: Capter 26 of “Principles and Methods of Quantum Information Technologies,”

  • 物性物理学ハンドブック

    ITOH KOHEI, 朝倉書店, 2012.05

    Scope: 295-306

  • 基礎からの量子光学

    ITOH KOHEI, ㈱オプトロニクス社, 2009.11

display all >>

Page Top ▲

Papers 【 Display / hide 】

  • Optimization of Optical Spin Readout of the Nitrogen-Vacancy Center in Diamond Based on Spin Relaxation Model

    Y. Nakamura, H. Watanabe, H. Sumiya, K. M. Itoh, K. Sasaki, J. Ishi-Hayase, and K. Kobayashi

    AIP Advances 12   055215 2022.05

    Research paper (scientific journal), Joint Work, Accepted

  • Electrical Control of the g tensor of the Fiest hole in a Silicon MOS Quantum Dot

    S. D. Liles, F. Martins, D. S. Miserev, A. A. Kiselev, I. D. Thorvaldson, M. J. Rendell, I. K. Jin, F. E. Hudson, M. Veldhorst, K. M. Itoh, O. P. Sushkov, T. D. Ladd, A. S. Dzurak, and A. R. Hamilton

    Phys. Rev. B  104   235303 2021.12

    Research paper (scientific journal), Accepted

  • Coherent Spin Qubit Transport in Silicon

    J. Yoneda, W. Huang, M. Feng, C. H. Yang, K. W. Chan, T. Tanttu, W. Gilbert, R. C. C. Leon, F. E. Hudson, K. M. Itoh, A. Morello, S. D. Bartlett, A. Laucht, A. Saraiva, and A. S. Dzurak

    Nature Communications  12   4114 2021.07

    Research paper (scientific journal), Joint Work, Accepted

  • Observation of Longitudinal Magnetic Fluctuations at a First-Order Ferromagnetic Quantum Phase Transition in UGe2

    Y. Noma, H. Kotegawa, T. Kubo, H. Tou, H. Harima, Y. Haga, E. Yamamoto, Y. Ōnuki, K. M. Itoh, A. Nakamura, Y. Homma, F. Honda, and D. Aoki

    J. Phys. Soc. Jpn. 90   073707 2021.06

    Research paper (scientific journal), Joint Work, Accepted

  • Bell-State Tomography in a Silicon Many-Electron Artificial Molecule

    R. C. C. Leon, C. H. Yang, J. C. C. Hwang, J. C. Lemyre, T. Tanttu, W. Huang, J. Y. Huang, F. E. Hudson, K. M. Itoh, A. Laucht, M. P.-Ladrière, A. Saraiva, and A. S. Dzurak

    Nature Communications 12   3228 2021.05

    Research paper (scientific journal), Joint Work, Accepted

display all >>

Page Top ▲

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

Page Top ▲

Reviews, Commentaries, etc. 【 Display / hide 】

  • A silicon quantum-dot-coupled nuclear spin qubit

    Hensen B., Wei Huang W., Yang C.H., Wai Chan K., Yoneda J., Tanttu T., Hudson F.E., Laucht A., Itoh K.M., Ladd T.D., Morello A., Dzurak A.S.

    Nature Nanotechnology (Nature Nanotechnology)  15 ( 1 ) 13 - 17 2020.01

    ISSN  17483387

    　View Summary

    © 2019, The Author(s), under exclusive licence to Springer Nature Limited. Single nuclear spins in the solid state are a potential future platform for quantum computing1–3, because they possess long coherence times4–6 and offer excellent controllability7. Measurements can be performed via localized electrons, such as those in single atom dopants8,9 or crystal defects10–12. However, establishing long-range interactions between multiple dopants or defects is challenging13,14. Conversely, in lithographically defined quantum dots, tunable interdot electron tunnelling allows direct coupling of electron spin-based qubits in neighbouring dots15–20. Moreover, the compatibility with semiconductor fabrication techniques21 may allow for scaling to large numbers of qubits in the future. Unfortunately, hyperfine interactions are typically too weak to address single nuclei. Here we show that for electrons in silicon metal–oxide–semiconductor quantum dots the hyperfine interaction is sufficient to initialize, read out and control single 29Si nuclear spins. This approach combines the long coherence times of nuclear spins with the flexibility and scalability of quantum dot systems. We demonstrate high-fidelity projective readout and control of the nuclear spin qubit, as well as entanglement between the nuclear and electron spins. Crucially, we find that both the nuclear spin and electron spin retain their coherence while moving the electron between quantum dots. Hence we envision long-range nuclear–nuclear entanglement via electron shuttling3. Our results establish nuclear spins in quantum dots as a powerful new resource for quantum processing.

  • Fidelity Benchmarks for Two-Qubit Gates in Silicon

    W. Huang, C. H. Yang, K. W. Chan, T. Tanttu, B. Hensen, R. C. C. Leon, M. A. Fogarty, J. C. C. Hwang, F. E. Hudson, K. M. Itoh, A. Morello, A. Laucht, and A.S. Dzurak

    Nature (Nature)  569 ( 7757 ) 532 - 536 2019.05

    Article, review, commentary, editorial, etc. (scientific journal), Joint Work,  ISSN  00280836

    　View Summary

    © 2019, The Author(s), under exclusive licence to Springer Nature Limited. Universal quantum computation will require qubit technology based on a scalable platform1, together with quantum error correction protocols that place strict limits on the maximum infidelities for one- and two-qubit gate operations2,3. Although various qubit systems have shown high fidelities at the one-qubit level4–10, the only solid-state qubits manufactured using standard lithographic techniques that have demonstrated two-qubit fidelities near the fault-tolerance threshold6 have been in superconductor systems. Silicon-based quantum dot qubits are also amenable to large-scale fabrication and can achieve high single-qubit gate fidelities (exceeding 99.9 per cent) using isotopically enriched silicon11,12. Two-qubit gates have now been demonstrated in a number of systems13–15, but as yet an accurate assessment of their fidelities using Clifford-based randomized benchmarking, which uses sequences of randomly chosen gates to measure the error, has not been achieved. Here, for qubits encoded on the electron spin states of gate-defined quantum dots, we demonstrate Bell state tomography with fidelities ranging from 80 to 89 per cent, and two-qubit randomized benchmarking with an average Clifford gate fidelity of 94.7 per cent and an average controlled-rotation fidelity of 98 per cent. These fidelities are found to be limited by the relatively long gate times used here compared with the decoherence times of the qubits. Silicon qubit designs employing fast gate operations with high Rabi frequencies16,17, together with advanced pulsing techniques18, should therefore enable much higher fidelities in the near future.

  • Preface to Special Topic: Defects in Semiconductors

    Yamamoto T., Fujiwara Y., Itoh K.

    Journal of Applied Physics (Journal of Applied Physics)  123 ( 16 )  2018.04

    ISSN  00218979

  • 固体量子情報デバイスの現状と将来展望-万能ディジタル量子コンピュータの実現に向けて

    阿部英介、伊藤公平

    応用物理 86 ( 6 ) 453 - 466 2017.06

    Article, review, commentary, editorial, etc. (scientific journal), Joint Work

  • スピントロニクス研究の原点からダイヤモンドでのトレンド，今後の展開まで

    阿部英介、伊藤公平

    NEW DIAMOND 33 ( 2 ) 3 - 6 2017.04

    Article, review, commentary, editorial, etc. (scientific journal), Joint Work

display all >>

Page Top ▲

Presentations 【 Display / hide 】

  • スピン緩和モデルを用いた窒素空孔中心スピンの光学的読み出し最適化

    中村祐貴、渡邊幸志、伊藤公平、佐々木健人、小林研介、早瀬潤子

    第69回応用物理学会春季学術講演会 (青山学院大学相模原キャンパス&オンライン) , 

    2022.03
    , 

    Oral presentation (general)

  • シリコンスピン量子ビットの位相コヒーレント輸送

    米田淳, W. Huang, M. Feng, C. H. Yang, K. W. Chan, T. Tanttu, W. Gilbert, R. C. C. Leon, F. E. Hudson, 伊藤公平, A. Morello, S. D. Bartlett, A. Laucht, A. Saraiva, and A. S. Dzurak

    日本物理学会2021年秋季大会物性, 

    2021.09
    , 

    Oral presentation (general)

  • 量子センサーを用いた交流磁場計測における非線形性と精度向上

    西村俊亮、五十川拓哉、伊藤公平、早瀬潤子、佐々木健人、小林研介

    日本物理学会2021年秋季大会物性, 

    2021.09
    , 

    Oral presentation (general)

  • 発光強度の重み付けによるダイヤモンド量子ビットの読み出し最適化

    中村祐貴、渡邊幸志、伊藤公平、佐々木健人、小林研介、早瀬潤子

    第82回応用物理学会秋季学術講演会 (名城大学＆オンライン) , 

    2021.09
    , 

    Oral presentation (general)

  • Quantum Sensors Along the Cylindrical Walls of Diamond Microwells

    1. T. Ishikawa, A. Yoshizawa, Y. Mawatari, H. Watanabe, J. Ishi-Hayase, and K. M. Itoh

    14th International Conference on New Diamond and Nano Carbons 2020/2021 (Virtual) , 

    2021.06
    , 

    Oral presentation (general)

display all >>

Page Top ▲

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

  • ダイヤモンド量子センサーを用いたハイゼンベルグ限界感度における核スピン検出

    2019.04
    -
    2022.03

    MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Principal investigator

  • Diamond Quantum Sensing

    2014.05
    -
    2019.03

    MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (S), Principal investigator

Page Top ▲

Works 【 Display / hide 】

  • 自分だけが知っている真理！

    ITOH KOHEI

    2011.12
    -
    Present
    , 

    Other, Single

  • 本音で語るアメリカ留学

    1999
    -
    Present
    , 

    Other, Single

Page Top ▲

Intellectual Property Rights, etc. 【 Display / hide 】

  • Date applied：   1999.03 

    Patent

Page Top ▲

Awards 【 Display / hide 】

  • 2018年度応用物理学会解説論文賞

    伊藤公平, 2018.09, 応用物理学会

    Type of Award： Award from Japanese society, conference, symposium, etc.

  • 応用物理学会フェロー表彰

    2015.07, 応用物理学会

  • 日本学術会議連携会員

    ITOH KOHEI, 2011.10, 日本学術会議

  • 日本学術振興会賞（JSPS PRIZE）

    ITOH KOHEI, 2009.03

  • 日本IBM科学賞

    ITOH KOHEI, 2006.11

display all >>

Page Top ▲
 

Courses Taught 【 Display / hide 】

  • SOLID STATE SCIENCE

    2022

  • PRESENTATION TECHNIQUE

    2022

  • INDEPENDENT STUDY ON FUNDAMENTAL SCIENCE AND TECHNOLOGY

    2022

  • GRADUATE RESEARCH ON FUNDAMENTAL SCIENCE AND TECHNOLOGY 2

    2022

  • GRADUATE RESEARCH ON FUNDAMENTAL SCIENCE AND TECHNOLOGY 1

    2022

display all >>

Page Top ▲
 

Social Activities 【 Display / hide 】

  • (国研)科学技術振興機構・文部科学省「量子科学技術イノベーション創出基盤調査分析業務」プログラムディレクター

    2018.07
    -
    2023.03

  • 文部科学省・科学技術・学術審議会専門委員

    2017.05
    -
    2019.02

  • 日本物理学会第73～74期代議員

    2017.03
    -
    2019.03

  • (国研)科学技術振興機構・CREST研究領域「量子状態の高度な制御に基づく革新的量子技術基盤の創出」領域アドバイザー

    2016.05
    -
    2020.03

  • (国研)科学技術振興機構・さきがけ研究領域「量子の状態制御と機能化」研究統括

    2016.04
    -
    2022.03

display all >>

Page Top ▲

Memberships in Academic Societies 【 Display / hide 】

  • Conference Co-Chair, International Sttering Committee, The 29th International Conference on Defects in Semiconductors, 

    2017.07
    -
    2017.08

  • Program Committee, The 7th International Conference on Physics and Applications of Spin-Related Phenomena in Semiconductors, 

    2016.08

  • 3rd Japan-Israel Binational Workshop on Quantum Phenomena, 

    2013.03

  • The 7th International Conference on Physics and Applications of Spin-Related Phenomena in Semiconductors, 

    2012.08

  • The 31st International Conference on Physics of Semiconductors, 

    2012.07
    -
    2012.08

display all >>

Page Top ▲

Committee Experiences 【 Display / hide 】

  • 2013.03

    Co-organiser, 3rd Japan-Israel Binational Workshop on Quantum Phenomena

  • 2012.10
    -
    Present

    Member, Working Group on Energy, International Univion of Pure and Applied Physics

  • 2012.09
    -
    Present

    誌友, アグネ技術センター「固体物理」

  • 2012.09
    -
    2014.03

    Committee Member, 東北大学電気通信研究所運営協議会

  • 2012.08

    Program Committee, The 7th International Conference on Physics and Applications of Spin-Related Phenomena in Semiconductors

display all >>

Page Top ▲