研究成果

Fast amplification and rephasing of entangled cat states in a qubit-oscillator system
Z. Xiao, T. Fuse, S. Ashhab, F. Yoshihara, K. Semba, M. Sasaki, M. Takeoka, and J. P. Dowling
PHYSICAL REVIEW A 99, 013827 (2019)
doi: 10.1103/PhysRevA.99.013827

Inversion of qubit energy levels in qubit-oscillator circuits in the deep-strong-coupling regime
Fumiki Yoshihara, Tomoko Fuse, Ziqiao Ao, Sahel Ashhab, Kosuke Kakuyanagi, Shiro Saito, Takao Aoki,  Kazuki Koshino, Kouichi Semba
Phys. Rev. Lett. 120, 183601 (2018)
doi: 10.1103/PhysRevLett.120.183601

Efficient Single-Photon Coupling from a Nitrogen-Vacancy Center Embedded in a Diamond Nanowire Utilizing an Optical Nanofiber
Yuya Yonezu, Kentaro Wakui, Kentaro Furusawa, Masahiro Takeoka, Kouichi Semba & Takao Aoki
Scientific Reports 7, Article number: 12985 (2017)
doi:10.1038/s41598-017-13309-z

Superradiant phase transition in the presence of parameter fluctuations
S. Ashhab and K. Semba ,
Physical Review A 95, 053833 (2017)  DOI: 10.1103/PhysRevA.95.053833

Characteristic spectra of circuit quantum electrodynamics systems from the ultrastrong to the deep strong coupling regime
F. Yoshihara, T. Fuse, S. Ashhab, K. Kakuyanagi, S. Saito, K. Semba
Physical Review A 95, 053824 (2017) DOI: 10.1103/PhysRev.95.053824

Simple method for fabrication of diamond nanowires by inductively coupled plasma reactive ion etching
Kentaro Wakui, Yuya Yonezu, Takao Aoki, Masahiro Takeoka, and Kouichi Semba
Japanese Journal of Applied Physics 56, 058005 (2017) DOI:10.7567/JJAP.56.058005

Superconducting qubit-oscillator circuit beyond the ultrastrong-coupling regime
Fumiki Yoshihara, Tomoko Fuse, Sahel Ashhab, Kosuke Kakuyanagi, Shiro Saito,
Kouichi Semba
Nature Physics 13, 44-47 (2017) doi:10.1038/nphys3906

Observation of collective coupling between an engineered ensemble of macroscopic artificial atoms and a superconducting resonator
Kosuke Kakuyanagi, Yuichiro Matsuzaki, Corentin Deprez, Hiraku Toida, Kouichi Semba, Hiroshi Yamaguchi, William J. Munro, and Shiro Saito
Phys. Rev. Lett. 117, 210503 (2016) DOI: 10.1103/PhysRevLett.117.210503

Hybrid quantum magnetic field sensor with an electron spin and a nuclear spin in diamond
Yuichiro Matsuzaki, Takaaki Shimo-Oka, Hirotaka Tanaka, Yasuhiro Tokura, Kouichi Semba, and Norikazu Mizuochi
Phys. Rev. A 94, 052330 (2016) DOI: 10.1103/PhysRevA.94.052330

Characterization and control of measurement induced dephasing on superconducting flux qubit with a Josephson bifurcation
K. Kakuyanagi, Y. Matsuzaki, T. Baba, H. Nakano, S. Saito, and K. Semba
J. Phys. Soc. Jpn. 85, 104801 (2016) DOI: 10.7566/JPSJ.85.104801

Optically detected magnetic resonance of high-density ensemble of NV centers in diamond
Y. Matsuzaki, H. Morishita, T. Shimooka, T. Tashima, K. Kakuyanagi, K. Semba, W. J. Munro, H. Yamaguchi, M. Norikazu, and S. Saito
J. Phys.: Condens. Matter 28, 275302 (2016) DOI: 10.1088/0953-8984/28/27/275302

Improving the lifetime of the nitrogen-vacancy-center ensemble coupled with a superconducting flux qubit by applying magnetic fields
Yuichiro Matsuzaki, Xiaobo Zhu, Kosuke Kakuyanagi, Hiraku Toida, Takaaki Shimooka, Norikazu Mizuochi, Kae Nemoto, Kouichi Semba, W. J. Munro, Hiroshi Yamaguchi, and Shiro Saito
Phys. Rev. A 91, 042329 (2015) DOI: 10.1103/PhysRevA.91.042329

Superconductor-Diamond Hybrid Quantum System
*K. Semba, F. Yoshihara, J. E. S. Johansson, X. Zhu, N. Mizuochi, William J. Munro,
S.Saito, K. Kakuyanagi, and Y. Matsuzaki
Principles and Methods of Quantum Information Technologies, Springer, Lecture Notes in Physics 911, Editors Y. Yamamoto & K. Semba, 515-538 (2016)

Analysis of the spectroscopy of a hybrid system composed of a superconducting flux qubit and diamond NV centers
H Cai, *Y Matsuzaki, K Kakuyanagi, H Toida1, X Zhu, N Mizuochi, K Nemoto, K Semba, W J Munro, S Saito and H Yamaguchi
J. Phys.: Condens. Matter 27, 1-15 (2015)

Observation of quantum Zeno effect in a superconducting flux qubit
*K. Kakuyanagi, T. Baba, Y. Matsuzaki, H. Nakano, S. Saito and K. Semba
New J. Phys. 17 (2015) 063035

Scalable quantum computation architecture using always-on Ising interactions via quantum feedforward
*Takahiko Satoh, *Yuichiro Matsuzaki, Kosuke Kakuyanagi, William J. Munro,
Koichi Semba, Hiroshi Yamaguchi, and Shiro Saito
Phys. Rev. A 91, 052329-1～6 (2015)

Improving the Coherence Time of a Quantum System via a Coupling to a Short-Lived System
*Y. Matsuzaki, X. Zhu, K. Kakuyanagi, H. Toida, T. Shimo-oka, N. Mizuochi, K. Nemoto,
K. Semba, W. J. Munro, H. Yamaguchi, S. Saito
Phys. Rev. Lett. 114, 120501-1～5 (2014)


Observation of dark states in a superconductor diamond quantum hybrid system
Xiaobo Zhu, Yuichiro Matsuzaki, Robert Amsu¨ss, Kosuke Kakuyanagi, Takaaki Shimo-Oka, Norikazu Mizuochi, Kae Nemoto, Kouichi Semba, William J. Munro & *Shiro Saito
Nature Communications, 3424, 1-6 (2014)

敖子嶠, 吉原文樹, 布施智子, 金鮮美, Sahel Ashhab, 角柳孝輔, 齊藤志郎, 設楽智洋, 越野和樹, 青木隆朗, 仙場浩一,
超強結合領域にある超伝導磁束量子ビット−コプレーナ共振器結合系での禁制遷移の観測,
日本物理学会2019年春季大会、九州大学(伊都キャンパス)、2019年3月14日-17日

設楽智洋, 馬場基彰, 吉原文樹, 布施智子, 仙場浩一, 越野和樹,
環境と結合した深強結合領域にある回路QED系の基底状態,
日本物理学会2019年春季大会、九州大学（伊都キャンパス、2019年3月14日-17日

加藤 悠輝，神谷 智大，金 鮮美，丘 偉，寺井 弘高，仙場 浩一, 山下 太郎，藤巻 朗,
超伝導量子ビットに向けた強磁性ジョセフソン接合における臨界電流密度の障壁層膜厚依存性の評価,
応用物理学会　2019年（平成31年）春季学術講演会,
2019年3月9日-12日, 東京工業大学　大岡山キャンパス

Tomoko Fuse , Zhihao Xiao , Sahel Ashhab , Fumiki Yoshihara , Kouichi Semba , Masahide Sasaki ,
Masahiro Takeoka , Jonathan P. Dowling,
Fast Amplification and Rephasing of Entangled Cat States in a Qubit-Oscillator System,
APS March Meeting 2019, Boston, USA, March 4-8, 2019

Fumiki Yoshihara , Sahel Ashhab , Tomoko Fuse , Kouichi Semba,
Cross-resonance-based readout scheme of a superconducting flux qubit,
APS March Meeting 2019, Boston, USA, March 4-8, 2019

Development of superconducting quantum circuit with π-junction qubit
Sunmi Kim, Fumiki Yoshihara, Tomoko Fuse, Wei Qiu, Ziqiao Ao, Hirotaka Terai, Kou-ichi Semba,
and Taro Yamashita
The 12th Superconducting SFQ VLSI Workshop (SSV 2019), Jan 16-17, 2019, NICT(Kobe)

Research activities on superconducting devices in NICT
Hirotaka Terai, Shigehito Miki, Wei Qiu, Shigeyuki Miyajima, Masahiro Yabuno, amd Fumihiro China
The 12th Superconducting SFQ VLSI Workshop (SSV 2019), Jan 16-17, 2019, NICT(Kobe)

Fabrication and Characterization of Ferromagnetic Josephson Junctions for π-shift Superconducting Flux Quantum Bit
Haruki Kato, Tomohiro Kamiya, Sunmi Kim, Wei Qiu, Akira Kawakami,
Hirotaka Terai, Koichi Semba, Taro Yamashita, and Akira Fujimaki
The 12th Superconducting SFQ VLSI Workshop (SSV 2019), Jan 16-17, 2019, NICT(Kobe)

環境と結合した深強結合領域にある量子ラビモデルの基底状態
設楽智洋, 馬場基彰, 吉原文樹, 布施智子, 仙場浩一, 越野和樹
第39回量子情報技術研究会 (QIT39)
2018年11月26-27日, 東京大学駒場リサーチキャンパス 先端科学技術研究センター

Kouichi Semba(Contributed Talk), Light-Matter Interaction ‘Beyond’ Strong-Coupling Regime
in Superconducting Circuit Quantum Electrodynamics, WINDS2018,
The Westin Hapuna Beach Resort, Kohala Coast, Hawaii, USA, Nov. 25-30, 2018

超伝導量子メタマテリアルの創成と制御
仙場浩一（招待講演）
JST-CREST「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」第３回シンポジウム
東京大学先端科学技術研究センター ENEOSホール 2018年11月21-22日

K. Semba(Invited)
Extremely strong light-matter interactions demonstrated in  circuit-QED,
KPS Fall Meeting, 2018.10.24-26  Changwon, Korea

パラメータ変動存在下での超放射相転移
仙場 浩一, アシュハブ サヘル
日本物理学会2018年秋季大会、同志社大学、2018年9月9日-12日

Aharonov-Casher効果を利用した超伝導磁束量子ビットのギャップエネルギーと循環電流
吉原文樹
日本物理学会2018年秋季大会、同志社大学、2018年9月9日-12日

量子ビット－調和振動子結合系におけるシュレディンガー猫状態の生成と増幅
布施 智子, Zhihao Xiao，Sahel Ashhab, 吉原 文樹, 仙場 浩一, 武岡 正裕, Jonathan P. Dowling
日本物理学会2018年秋季大会、同志社大学、2018年9月9日-12日

π接合を用いた超伝導量子メタマテリアル
金鮮美, 山下太郎, 吉原文樹, 布施智子, 丘偉, 敖子嶠, 寺井弘高, 仙場浩一
日本物理学会2018年秋季大会、同志社大学、2018年9月9日-12日

Kouichi Semba(Invited)
第8回半導体/超伝導体量子効果と量子情報の夏期研修会
Light-Matter Interaction beyond `Strong Coupling' in Circuit Quantum Electrodynamics
サンバレー那須、2018年9月4-6日

Kouichi Semba(Invited)
Light-Matter Interaction beyond 'Strong Coupling'in Circuit Quantum Electrodynamics
International Workshop on "Fundamental Problems in Mathematical and Theoretical Physics"
Waseda University, Nishi-Waseda Campus, July 16-21, 2018

Kouichi Semba(Invited)
Various Strong Coupling of Light-Matter Interaction in the Superconducting Quantum Circuit
The International Workshop on Recent Progress in Superconductivity (IWRS2018),
Pyeongchang, Korea, July 9-11, 2018

光ｼﾌﾄを受けた磁束量子ﾋﾞｯﾄにおけるｴﾈﾙｷﾞｰ準位反転の観測
吉原文樹
日本物理学会 第73回年次大会（2018年）、東京理科大学、2018年3月22日-25日

量子ビット - 調和振動子結合回路の超強領域における時間領域測定
布施智子
日本物理学会 第73回年次大会（2018年）東京理科大学、2018年3月22日-25日

Inversions of qubit energy levels in deep-strongly-coupled qubit-oscillator circuits
F. Yoshihara, T. Fuse, Z. Ao, S. Ashhab, K. Kakuyanagi, S. Saito, T. Aoki,
K. Koshino, and K. Semba
APS March Meeting 2018, Los Angels, March 5–9, 2018

Superradiance phase transition in the presence of parameter fluctuations
S. Ashhab, K. Semba
APS March Meeting 2018, Los Angels, March 5–9, 2018

超伝導人工原子とマイクロ波真空ゆらぎからなる新しい「分子」状態
仙場浩一(招待講演), 未来ICTシンポジウム2018, 東京ビッグサイト, 2018年2月14日

Superconducting qubit-oscillator circuit beyond the ultrastrong-coupling regime
Fumiki Yoshihara(Invited), Tomoko Fuse, Sahel Ashhab, Kosuke Kakuyanagi, Shiro Saito, Kouichi
Semba
ISS2017, IINO Hall&Conference Center, Tokyo, Japan, Dec. 13-17, 2017

Superconducting quantum metamaterial
Kouichi Semba (Invited)
The meeting of JST-CREST "Creation of an innovative quantum technology platform based on the advanced control of quantum states"
Kyoto University, Dec. 7-8, 2017

Inversion of qubit energy levels in qubit-oscillator circuits in the deep-strong-coupling regime
Fumiki Yoshihara, Tomoko Fuse, Ziqiao Ao, Sahel Ashhab, Kosuke Kakuyanagi, Shiro Saito, Takao Aoki,
Kazuki Koshino, Kouichi Semba,
The meeting of JST-CREST "Creation of an innovative quantum technology platform based on the advanced control of quantum states"
Kyoto University, Dec. 7-8, 2017

Time-domain measurements and control pf a qubit-oscillator coupled circuit in ultra-strong coupling regime
Tomoko Fuse, Fumiki Yoshihara, , Sahel Ashhab, Kosuke Kakuyanagi, Shiro Saito, Kouichi Semba
The meeting of JST-CREST "Creation of an innovative quantum technology platform based on the advanced control of quantum states"
Kyoto University, Dec. 7-8, 2017

超伝導人工原子と電磁場の相互作用はどこまで強くできるか?
仙場浩一（招待講演）, 応用物理学会 (超伝導分科会 第56回研究会), アットビジネスセンター東京駅, 2017年12月1日

Superradiance phase transition in the presence of parameter fluctuations
Kouichi Semba(Contributed Talk), S. Ashhab
WINDS2017, Hapuna Beach Prince Hotel Kohala Coast, Hawaii, USA, Nov. 26-Dec. 1, 2017

Superconducting qubit-oscillator circuit beyond the ultrastrong-coupling regime
Fumiki Yoshihara(Contributed Talk), Tomoko Fuse, Sahel Ashhab, Kosuke Kakuyanagi, Shiro Saito, Kouichi
Semba
WINDS2017, Hapuna Beach Prince Hotel Kohala Coast, Hawaii, USA, Nov. 26-Dec. 1, 2017

F. Yoshihara, T. Fuse, Z. Ao, S. Ashhab, K. Kakuyanagi, S. Saito, T. Aoki, and K. Semba
Twists of qubit energies in deep-strongly-coupled qubit-oscillator circuits
ISNTT2017
NTT Basic Reasearch Laboratories, Nov, 13-17, 2017

Tomoko Fuse, Fumiki Yoshihara, Sahel Ashhab, Kosuke Kakuyanagi, Shiro Saito, and Kouichi Semba
Parity symmetry and selection rules in a qubit-harmonic oscillator coupled system
ISNTT2017
NTT Basic Reasearch Laboratories, Nov, 13-17, 2017

Z. Ao, F. Yoshihara, T. Fuse, S. Ashhab, K. Kakuyanagi, S. Saito, T. Aoki, and K. Semba
Giant Lamb shift observed in deep-strongly-coupled superconducting qubit-oscillator circuit
ISNTT2017
NTT Basic Reasearch Laboratories, Nov, 13-17, 2017

Twists of qubit energy levels in deep-strongly-coupled qubit-oscillator circuits
Fumiki YOSHIHARA, Tomoko Fuse, Ao Ziqiao, Sahel Ashhab, Kosuke Kakuyanagi, Shiro Saito, Takao, Aoki,
and Kouichi Semba
Quantum Theory&Technology Un-official Meeting 2017
Oct. 7-8, 2017, Hokkaido-University

F. Yoshihara,  T. Fuse, S. Ashhab, K. Kakuyanagi, S. Saito, and K. Semba
Characteristic spectra of circuit quantum electrodynamics systems from the ultrastrong to
the deep-strong-coupling regime
The Physical Society of Japan 2017 Autumn Meeting
Sep. 21-24, 2017, Iwate University

T. Fuse, F. Yoshihara, S. Ashhab, K. Kakuyanagi, S. Saito, K. Semba
Symmetry and selection rules in a qubit-oscillator coupled system
The Physical Society of Japan 2017 Autumn Meeting
Sep. 21-24, 2017, Iwate University

Z. Ao, F. Yoshihara, T. Fuse, S. Ashhab, K. Kakuyanagi, S. Saito, T. Aoki, K. Semba
Giant Lamb shift observed in deep-strongly-coupled superconducting qubit-oscillator
circuit
The Physical Society of Japan 2017 Autumn Meeting
Sep. 21-24, 2017, Iwate University

F. Yoshihara,  T. Fuse, S. Ashhab, K. Kakuyanagi, S. Saito, and K. Semba
Characteristic spectra of circuit quantum electrodynamics systems from the ultrastrong to
the deep-strong-coupling regime
International Symposium on Hybrid Quantum Sytems 2017 (HQS2017)
Sep. 10-13, 2017, Miyagi-Zao

T. Fuse, F. Yoshihara, S. Ashhab, K. Kakuyanagi, S. Saito, K. Semba
Symmetry and selection rules in a qubit-oscillator coupled system
International Symposium on Hybrid Quantum Sytems 2017 (HQS2017)
Sep. 10-13, 2017, Miyagi-Zao

Z. Ao, F. Yoshihara, T. Fuse, S. Ashhab, K. Kakuyanagi, S. Saito, T. Aoki, K. Semba
Giant Lamb shift observed in deep-strongly-coupled superconducting qubit-oscillator
circuit
International Symposium on Hybrid Quantum Sytems 2017 (HQS2017)
Sep. 10-13, 2017, Miyagi-Zao

Kouichi Semba(Invited)
New Light-Matter Ground State in the Deep Strong Coupling Regime
EDISON 20, July 17-21, 2017, Hyatt Regency Hotel, Buffalo, NY, USA

Kouichi Semba(Invited)
Superconducting qubit–oscillator circuit in the extremely strong-coupling
International Workshop on Quantum Technologies (QTech2017), June 12-13, 2017, The Univ. of Tokyo

Kouichi Semba(Invited)
Superconducting qubit–oscillator circuit beyond the ultrastrong-coupling regime
Symposium on Atomic, Molecular, and Optical Sciences 14, June 30-July 1, 2017, The Univ. of Electro-Communications

Kouichi Semba (invited)
Quantum Hybrid System and NV Centers in Diamond
The 64th JSAP Spring Meeting 2017, March 14-17, Pacifico Yokohama

T. Fuse, F. Yoshihara, S. Ashhab, K. Semba
Deep strong coupling in a circuit QED system - huge Lamb shift -
American Physics Society (APS) March Meeting 2017, Ernest N. Morial Convention Center, New Orleans, USA, March 13-17, 2017.

F. Yoshihara, T. Fuse, K. Semba, S. Ashhab
Characteristic spectra of circuit quantum electrodynamics systems from the ultrastrong to the deep strong coupling regime
American Physics Society (APS) March Meeting 2017, Ernest N. Morial Convention Center, New Orleans, USA, March 13-17, 2017.

T. Fuse (invited), F. Yoshihara, S. Ashhab, Kosuke Kakuyanagi, Shiro Saito, K. Semba,
Superconducting Qubit-Oscillator Circuit in the Deep Strong Coupling Regime ~Experiments~
Interdisciplinary Workshop on Quantum Device (IWQD2017), Tokyo, 6-8 March, 2017

T. Fuse (invited), F. Yoshihara, S. Ashhab, K. Semba
Superconducting Qubit-Oscillator Circuit in the Deep Strong Coupling Regime
JSAP Workshop on Quantum Information and Related Fields, NII, Tokyo, Japan, March 2-3, 2017.

T. Fuse (invited), F. Yoshihara, S. Ashhab, K. Semba
Superconducting qubit-oscillator circuit in the deep strong coupling regime
Workshop on Virtual Photons in ultra-strong coupled Systems, RIKEN, Saitama, Japan, Janurary 23-26, 2017.

Fumiki Yoshihara (Invited)
Characteristic spectra of circuit quantum electrodynamics systems from the ultrastrong to the deep strong coupling regime
Workshop on Virtual Photons in ultra-strong coupled Systems, RIKEN, Saitama, Japan, Janurary 23-26, 2017.

Kouichi Semba (Invited)
Stable ‘Molecular’ State of Photons and Artificial Atom
International Workshop on Nano-Spin Conversion Science and Quantum Spin Dynamics(NSCS-QSD) October 12-15, 2016,
The University of Tokyo

Fumiki Yoshihara (Invited)
Superconducting qubit-oscillator circuit beyond the ultrastrong-coupling regime
International Workshop on Ultra-Strong Light-Matter Interactions: theory and applications to quantum information, 19-21 September 2016,
Bilbao, Spain

超伝導人工原子・調和振動子　超強結合系
布施智子
第63回応用物理学会春季学術講演会(招待講演), 2016年3月22日, 東京工業大学 大岡山キャンパス

Deep strong coupling in a circuit QED system (1) – Introduction –
Kouichi Semba , Tomoko Fuse , Fumiki Yoshihara , Sahel Ashhab
American Physical Society March Meeting 2016 ,March 14–18, 2016, Baltimore, Maryland

Deep strong coupling in a circuit QED system (2) – experiment –
Tomoko Fuse , Fumiki Yoshihara , Sahel Ashhab , Kouichi Semba
American Physical Society March Meeting 2016 ,March 14–18, 2016, Baltimore, Maryland

Deep strong coupling in a circuit QED system (3) – data and analysis –
Fumiki Yoshihara , Tomoko Fuse , Kouichi Semba , Sahel Ashhab
American Physical Society March Meeting 2016 ,March 14–18, 2016, Baltimore, Maryland

Physics of Superconducting quantum circuit – perspective of strong coupling and beyond
Kouichi Semba, IWQD2015 (招待講演), Oct.13-14, 2015, NII

Superconducting Flux Qubit & Electron Spin Ensemble in Diamond Hybrid Quantum System, K. Semba
The 67th Fujihara seminar: “Real-time dynamics of physical phenomena and manipulation
by external field” （招待講演）, September 25, 2014, Tomakomai, Hokkaido, Japan

超伝導量子ビットとマイクロ波を使った実験
吉原 文樹
京都大学基礎物理学研究所 研究会 「若手のための量子情報基礎セミナー」（招待講演）
2014年8月10日～11日, 京都大学基礎物理学研究所 湯川記念館


T. Fuse, Fumiki Yoshihara, Kouichi Semba
Josephson bifurcation amplifier, flux qubit and Josephson parametric amplifier
Gordon Research Conference: Quantum Science 2014, 26 July 2014,
Stonehill College, MA, USA

仙場浩一
巨視的量子ハイブリッド系
QIT29(招待講演), 2013年11月19日, 早稲田大学西早稲田キャンパス

Challenges & Trends of Quantum Information Technology in Japan
Kouichi Semba
The 1st Japan-Canada IT Symposium (招待講演), Oct 9, 2013, Embassy of Canada, Japan

Kouichi Semba [invited]
"Coherent Coupling of a Superconducting Flux Qubit to an Electron Spin Ensemble in Diamond"
Gordon Research Conference: Quantum Science 2012, Stonehill College, MA, USA, 12-17 August 2012 https://www.grc.org/programs.aspx?year=2012&program=quantsci
 

• http://www.ntt.co.jp/news2011/1110/111012a.html
• http://www.brl.ntt.co.jp/J/2011/10/latest_topics_201110130201.html

• http://www.ntt.co.jp/journal/1201/files/jn201201063.pdf