Theory of quantum computer using ferromagnetic Josephson junctions

• Project/Area Number: 19710085
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Single-year Grants
• Research Field: Nanostructural science
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: KAWABATA Shiro National Institute of Advanced Industrial Science and Technology, ナノテクノロジー研究部門, 主任研究員 (30356852)
• Project Period (FY): 2007 – 2008
• Project Status: Completed (Fiscal Year 2008)
• Budget Amount: ¥3,790,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥390,000); Fiscal Year 2008: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2007: ¥2,100,000 (Direct Cost: ¥2,100,000)
• Keywords: 量子コンピュータ / スピントロニクス / ジョセフソン効果 / 磁性半導体 / 巨視的量子トンネル現象 / 強磁性絶縁体 / ジョセフソン接合 / メゾスコピック系 / 巨視的量子トンネル効果 / 量子情報 / グリーン関数法

Research Abstract

本研究においては、強磁性絶縁体を用いたジョセフソン接合の量子輸送及び巨視的量子ダイナミクスの理論・数値解析を行い、その基礎物性の予測及びコヒーレンス評価行う。そして、強磁性絶縁体ジョセフソン接合が量子ビットとして有望な素子となりうることを明らかにする。

Research Products

• [Journal Article] Effect of d-f hybridization on the Josephson current through Eu-chalcogenides (2009)
  • Author(s): S. Kawabata, Y. Asano, Y. Tanaka, and S. Kashiwaya
  • Journal Title: Physica C (受理)
  • Peer Reviewed
• [Journal Article] Theory of two-dimensional macroscopic quantum tunneling in a Josephson junction coupled with an LC circuit (2009)
  • Author(s): S. Kawabata, T. Kato, and T. Bauch
  • Journal Title: Journal of Physics : Conference Series 150
  • Peer Reviewed
• [Journal Article] Cooper pairtransport and macroscopic quantum dynamics in Josephson junctions through ferromagnetic insulators (2008)
  • Author(s): S. Kawabata, Y. Asano, Y. Tanaka, S. Kashiwaya and A. A. Golubov
  • Journal Title: Physica C 468 Pages: 701-704
  • Peer Reviewed
• [Journal Article] Cooper pair transport and macroscopic quantum dynamics in Josephson junctions through ferromagnetic insulators (2008)
  • Author(s): S. Kawabata, Y. Asano, Y. Tanaka, S. Kashiwaya and A. A. Golubov
  • Journal Title: Physica C 468 Pages: 701-704
  • Peer Reviewed
• [Journal Article] Cooper pair transport and macroscopic quantum dynamics in Josephson junctions through ferromagnetic insulators (2008)
  • Author(s): S. Kawabata, Y. Asano, Y. Tanaka, S. Kashiwaya and A. A. Golubov
  • Journal Title: Physica C 468 Pages: 701-704
  • Peer Reviewed
• [Journal Article] Possible observation of energy level quantization in an in trinsic Josephson junction (2008)
  • Author(s): H. Kashiwaya, T. Matsumoto, S. Kashiwaya, H. Shibata, H. Eisaki, Y. Yoshida, S. Kawabata, and Y. Tanaka
  • Journal Title: Physica C 468 Pages: 1919-1921
  • Peer Reviewed
• [Journal Article] Switching dynamics of BiSrCaCuO intrinsic Josephson junctions: macroscopic quantum tunneling and heating effect (2008)
  • Author(s): H. Kashiwaya, T. Matsumoto, S. Kashiwaya, H. Shibata, H. Eisaki, Y. Yoshida, S. Kawabata, and Y. Tanaka
  • Journal Title: J. Phys. Soc. Jpn. 77
  • Peer Reviewed
• [Journal Article] Macroscopic quantum tunneling and quasiparticle-tunneling blockade effect in s-wave/d-wave hybrid junctions (2007)
  • Author(s): S. Kawabata, A. A. Golubov, Ariando, C. J. M. Verwijs, H. Hilgenkamp, and J. R. Kirtley
  • Journal Title: Physical Review B 76
  • Peer Reviewed
• [Journal Article] Theory of Macroscopic Quantum Tunneling in High-Tc c-Axis Josephson Junction (2007)
  • Author(s): T. Yokoyama, S. Kawabata, T. Kato, and Y. Tanaka
  • Journal Title: Physical Review B 76
  • Peer Reviewed
• [Journal Article] Macroscopic Quantum Tunneling in piJosephson Junctions with Insulating Ferromagnets and its Application to Phase Qubits (2007)
  • Author(s): S. Kawabata and A. A. Golubov
  • Journal Title: Physica E 40 Pages: 386-389
  • Peer Reviewed
• [Journal Article] Macroscopic quantum tunneling and quasiparticle-tunneling blockade effect in s-wave/d-wave hybrid junctions (2007)
  • Author(s): S.Kawabata, A. A.Golubov, Ariando, C. J.M. Verwijs, H. Hilgenkamp, and J.R. Kirtley
  • Journal Title: Physical Review B 76
  • Peer Reviewed
• [Journal Article] MQT observation in Bi2212 intrinsic Josephson junctions (2007)
  • Author(s): S.Kashiwaya, T.Matsumoto, H.Kashiwaya, H.Shibata, H.Eisaki, Y.Yoshida, S.Kawabata, and Y.Tanaka
  • Journal Title: Physica C 460-462 Pages: 1432-1433
  • Peer Reviewed
• [Journal Article] Quantum Dissipative Dynamics in Nanostructure d-wave Josephson Junctions (2007)
  • Author(s): S.Kawabata, A. A.Golubov, Y.Tanaka and S.Kashiwaya
  • Journal Title: Physica C 460-462 Pages: 1479-1480
  • Peer Reviewed
• [Journal Article] Theory of Macroscopic Quantum Tunneling in Nb/Au/YBCO Josephson Junctions (2007)
  • Author(s): S.Kawabata, A. A.Golubov, Ariando, C.J. M.Verwijs, and H.Hilgenkamp
  • Journal Title: Physica C 463-465 Pages: 80-30
  • Peer Reviewed
• [Journal Article] Theory of macroscopic quantumcoherence in d-wave superconductor junctions (2007)
  • Author(s): T.Umeki, T.Kato, T.Yokoyama, Y.Tanaka, S.Kawabata, and S.Kashiwaya
  • Journal Title: Physica C 463-465 Pages: 157-160
  • Peer Reviewed
• [Journal Article] Theory of Macroscopic Quantum Tunneling in High-Tc c-Axis Josephson Junction (2007)
  • Author(s): T.Yokoyama, S.Kawabata, T.Kato, and Y.Tanaka
  • Journal Title: Physical Review B 76
  • Peer Reviewed
• [Journal Article] Macroscopic Quantum Tunneling in pi Josephson Junctions with Insulating Ferromagnets and its Application to Phase Qubits (2007)
  • Author(s): S.Kawabata and A.A.Golubov
  • Journal Title: Physica E 40 Pages: 386-389
  • Peer Reviewed
• [Presentation] Atomic-scale 0-π transition in ferromagnetic-insulator based Josephson junctions (2009)
  • Author(s): S. Kawabata, Y. Asano, Y. Tanaka, and S. Kashiwaya
  • Organizer: Joint JSPS-NES International Conference on Nanoscience and Engineering in Superconductivity
  • Place of Presentation: つくば市
  • Year and Date: 2009-03-24
• [Presentation] Josephson π-junction through spintronics materials (2009)
  • Author(s): S. Kawabata, Y. Asano, Y. Tanaka, and S. Kashiwaya
  • Organizer: International Symposium on Nanoscience and Quantum Physics
  • Place of Presentation: 東京
  • Year and Date: 2009-02-23
• [Presentation] Theory of Josephson effect through spintronics materials (2009)
  • Author(s): S. Kawabata, Y. Asano, Y. Tanaka, and S. Kashiwaya
  • Organizer: International Symposium on Nanoscale Transport and Technology (NTT2009)
  • Place of Presentation: 厚木市
  • Year and Date: 2009-01-12
• [Presentation] Introduction to Macroscopic Quantum Tunneling in Josephson Junction Systems : From BCS to High-Tc Superconductors (2008)
  • Author(s): S. Kawabata,
  • Organizer: 3rd International Autumn Seminar on Nanoscience and Engineering in Superconductivity for Young Scientists
  • Place of Presentation: 東京
  • Year and Date: 2008-11-30
• [Presentation] Theory of π -junction using spin filtering barrier (2008)
  • Author(s): S. Kawabata
  • Organizer: The 23rd Nishinomiya-Yukawa Memorial International Workshop Spin Transport in Condensed Matter
  • Place of Presentation: 京都市
  • Year and Date: 2008-11-11
• [Presentation] Theory of pi-junction using spin filtering barrier (2008)
  • Author(s): S. Kawabata,
  • Organizer: The 23rd Nishinomiya-Yukawa Memorial International Workshop Spin Transport in Condensed Matter
  • Place of Presentation: 京都
  • Year and Date: 2008-11-11
• [Presentation] Effect of s-f hybridization on the Josephson current through spin filters (2008)
  • Author(s): S. Kawabata, Y. Asano, Y. Tanaka, and S. Kashiwaya
  • Organizer: 21st International Symposium on Superconductivity (ISS2008)
  • Place of Presentation: つくば市
  • Year and Date: 2008-10-29
• [Presentation] Theory of Dissipative Quantum Dynamics in High-Tc Superconductor Josephson Junctions (2008)
  • Author(s): S. Kawabata,
  • Organizer: Dynamics and Manipulation of Quantum Systems
  • Place of Presentation: 東京
  • Year and Date: 2008-10-20
• [Presentation] Theory of Macroscopic Quantum Dynamics in High-Tc Josephson Junctions (2008)
  • Author(s): S. Kawabata,
  • Organizer: The 9th International Symposium on the Foundations of Quantum Mechanics in the Light of New Technology (ISQM-Tokyo 2008)
  • Place of Presentation: 埼玉県鳩山市
  • Year and Date: 2008-08-27
• [Presentation] Theory of π -junction using spin filtering barriers (2008)
  • Author(s): S. Kawabata
  • Organizer: XXXII International Workshop on Condensed Matter Theories (CMT32)
  • Place of Presentation: Loughborough/イギリス
  • Year and Date: 2008-08-15
• [Presentation] Theory of pi-junction using spin filtering barriers (2008)
  • Author(s): S. Kawabata,
  • Organizer: XXXII International Workshop on Condensed Matter Theories (CMT32)
  • Place of Presentation: Loughborough/UK
  • Year and Date: 2008-08-15
• [Presentation] Two-dimensional Macroscopic quantum dynamics in YBCO Josephson Junctions (2008)
  • Author(s): S. Kawabata,
  • Organizer: XXXII International Workshop on Condensed Matter Theories (CMT32)
  • Place of Presentation: Loughborough/UK
  • Year and Date: 2008-08-15
• [Presentation] Theory of Macroscopic quantum phenomena in unconventional d-wave Josephson junctions (2007)
  • Author(s): S. Kawabata,
  • Organizer: Frontiers of Josephson Physics and Nanoscience
  • Place of Presentation: Palinuro/Italy
  • Year and Date: 2007-09-25
• [Presentation] Cooper pair transport and macroscopic quantum dynamics in Josephson junctions through ferromagnetic insulators (2007)
  • Author(s): S. Kawabata, and Y. Asano
  • Organizer: Joint ESF and JSPS Conference on Vortex Matter in Nanostructured Superconductors
  • Place of Presentation: Rhodes/ギリシャ
  • Year and Date: 2007-09-13
• [Presentation] Cooper pair transport and macroscopic quantum dynamics in Josephson junctions through ferromagnetic insulators (2007)
  • Author(s): S. Kawabata, and Y. Asano,
  • Organizer: Joint ESF and JSPS Conference on Vortex Matter in Nanostructured Superconductors
  • Place of Presentation: Rhodes/Greece
  • Year and Date: 2007-09-13
• [Presentation] Macroscopic Quantum Phenomena in Small High-Tc Josephson Junctions (2007)
  • Author(s): S. Kawabata
  • Organizer: Linnaeus Summer School on Nanophysics
  • Place of Presentation: Orestrand/Sweden
  • Year and Date: 2007-08-19
• [Presentation] π junction formation in Josephson junctions with ferromagnetic insulator: physics and qubit application (2007)
  • Author(s): S. Kawabata
  • Organizer: Lorentz Workshop on Physics of Nanoscale Superconducting Heterostructures
  • Place of Presentation: Leiden/オランダ
  • Year and Date: 2007-07-02
• [Presentation] Pi junction formation in Josephson junctions with ferromagnetic insula (2007)
  • Author(s): S. Kawabata
  • Organizer: Lorentz Workshop on Physics of Nanoscale Super conducting Heterostructures
  • Place of Presentation: Leiden Univ./The Netherlands
  • Year and Date: 2007-07-02
• [Presentation] Theory of quantum dissipation in small High-Tc Josephson junctions (2007)
  • Author(s): S. Kawabata
  • Organizer: Lorentz Workshop on quantum effects in arrays of nanocrystals
  • Place of Presentation: Leiden Univ./The Netheds
  • Year and Date: 2007-04-27
• [Presentation] Macroscopic Quantum Phenomena in Josephson Junctions: From BCS to High-Tc Superconductors (2007)
  • Author(s): S. Kawabata,
  • Organizer: International Autumn Seminar on Nanoscience and Engineering in Superconductivity for Young Scientists
  • Place of Presentation: 那須高原/栃木