• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

キャリア・ドープしたスピンチューブにおけるカイラリティ誘起超伝導の理論的研究

Research Project

Project/Area Number 19014019
Research Category

Grant-in-Aid for Scientific Research on Priority Areas

Allocation TypeSingle-year Grants
Review Section Science and Engineering
Research InstitutionJapan Atomic Energy Agency

Principal Investigator

坂井 徹  Japan Atomic Energy Agency, 量子ビーム応用研究部門, 研究主幹 (60235116)

Co-Investigator(Kenkyū-buntansha) 岡本 清美  東京工業大学, 大学院・理工学研究科, 助教 (40152342)
大塚 雄一  日本原子力研究開発機構, 協力研究員 (30390652)
Project Period (FY) 2007 – 2008
Project Status Completed (Fiscal Year 2008)
Budget Amount *help
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 2008: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2007: ¥1,300,000 (Direct Cost: ¥1,300,000)
Keywordsスピンチューブ / キャリア・ドープ / 超伝導 / カイラリティ / スピンギャップ
Research Abstract

スピンチューブとは、N本の反強磁性量子スピン鎖を鎖間方向に反強磁性交換相互作用で周期的に結合した系である。そのうち最も量子効果とフラストレーションの強い3本鎖スピンチューブについて焦点を絞り、キャリア・ドープした場合に超伝導を引き起こす起源となるスピンギャップについて、数値的厳密対角化と密度行列繰り込み群により、理論的に研究した。
従来の研究から、断面が正三角形の3本鎖スピンチューブは、大きなスピンギャップを持つことが知られているが、断面を二等辺三角形に変形したときにこのスピンギャップが急激に消失する量子相転移がきることが予測されていた。本年度の研究では、この量子相転移を理論的に予言できるはバード模型に基づく有効理論、及びハイゼンベルグ模型の数値対角化と密度行列繰り込み群による精度の高い大規模数値解析により、スピンギャップの正確な理論的相図を得ることに成功した。
また この3本鎖スピンチューブにキャリア・ドープした場合に、カイラリティの自由度を媒介にした超伝導が起きる可能性を探るため、ハバード模型の数値対角化と密度行列繰り込み群により解析した結果、いくつかの特徴的なパラメータでは、キャリアーのペアリングを示唆する、束縛エネルギーの減少やRVB相関関数の増大が起きることが判明した。

Report

(2 results)
  • 2008 Annual Research Report
  • 2007 Annual Research Report
  • Research Products

    (34 results)

All 2009 2008 2007 Other

All Journal Article (16 results) (of which Peer Reviewed: 16 results) Presentation (16 results) Remarks (2 results)

  • [Journal Article] Phase competitions and coexistences in quasi-one-dimensional molecular conductors-exact diagonalization study2009

    • Author(s)
      Y. Otsuka
    • Journal Title

      Physica B: Condensed Matter 404

      Pages: 479-181

    • Related Report
      2008 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Field-Induced Incommensurate Order and Possible Supersolid in the S=1/2 Frustrated Diamond Chain2009

    • Author(s)
      T. Sakai
    • Journal Title

      Journal of Physics: Conference Series 145

    • Related Report
      2008 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Ground-State Phase Diagram of an (S, S')=(1, 2) Spin-Alternating Chain with Competing Single-Ion Anisotropies2009

    • Author(s)
      T. Tonegawa
    • Journal Title

      Journal of Physics: Conference Series 145

    • Related Report
      2008 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Two-step quantum spin flop transition in spin ladders2009

    • Author(s)
      T. Sakai
    • Journal Title

      Journal of Physics: Conference Series 150

    • Related Report
      2008 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Quantum phase transitions of the asymmetric three-leg spin tube2008

    • Author(s)
      T. Sakai
    • Journal Title

      Physical Review B 78

    • Related Report
      2008 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Possible Mechanism of Charge Stripe Formation Based on the Ring Exchange Interaction2008

    • Author(s)
      T. Sakai
    • Journal Title

      Physica C 468

      Pages: 1163-1165

    • Related Report
      2008 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Numerical Diagonalization Study on a Phonon-assisted Hole Pairing Mechanism of an Extended t-J Holstein Model2008

    • Author(s)
      T. Sakai
    • Journal Title

      Journal of Physics: Conference Series 108

    • Related Report
      2008 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Finite-temperature phase diagram of quasi-one-dimensional molecular conductors: quantum Monte Carlo study2008

    • Author(s)
      Y. Otsuka
    • Journal Title

      Journal of Physical Society of Japan 77

    • Related Report
      2008 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Mott insulating state in incommensurate molecular conductor2008

    • Author(s)
      H. Seo
    • Journal Title

      Journal of Physics: Conference Series 132

    • Related Report
      2008 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Quantum Spin Flop Transition in Nanowire Ferrimagnets2007

    • Author(s)
      T. Sakai
    • Journal Title

      Physica E 40

      Pages: 359-362

    • Related Report
      2007 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Field-Induced Incommensurate Order in Frustrated Spin Ladder2007

    • Author(s)
      T. Sakai
    • Journal Title

      Journal of Physic: Condensed Matter 19

    • Related Report
      2007 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Quantum Phase Transition in the Three-Leg Spin Nanotube2007

    • Author(s)
      T. Sakai
    • Journal Title

      Journal of Magnetism and Magnetic Materials 310

    • Related Report
      2007 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Interplay between the Trimerization and Frustration in Spin-1/2 Distorted Diamond Type Spin Chain with the XXZ Anisotropy2007

    • Author(s)
      K. Okamoto
    • Journal Title

      Journal of Magnetism and Magnetic Materials 310

    • Related Report
      2007 Annual Research Report
    • Peer Reviewed
  • [Journal Article] One-Third Magnetization Plateau in an Anisotropic (S,S')=(1,2) Spin-Alternating Chain2007

    • Author(s)
      T. Tonegawa
    • Journal Title

      Journal of the Physical Society of Japan 76

    • Related Report
      2007 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Finite-Field Ground State of an S=1 Zigzag Ladder2007

    • Author(s)
      T. Tonegawa
    • Journal Title

      Journal of Magnetism and Magnetic Materials 310

    • Related Report
      2007 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Vector chirality and inhomogeneous magnetization in frustrated spin tubes in high magnetic fields2007

    • Author(s)
      M. Sato
    • Journal Title

      Physical Review B 75

    • Related Report
      2007 Annual Research Report
    • Peer Reviewed
  • [Presentation] スピンナノチューブ:最近の理論的発展2009

    • Author(s)
      坂井徹
    • Organizer
      日本物理学会、領域3,8,11合同シンポジウム
    • Place of Presentation
      東京
    • Year and Date
      2009-03-28
    • Related Report
      2008 Annual Research Report
  • [Presentation] Quantum Phase Transition of the Asymmetric Spin Tube2009

    • Author(s)
      T. Sakai
    • Organizer
      American Physical Sosiety March Meeting
    • Place of Presentation
      Pittsburgh
    • Year and Date
      2009-03-16
    • Related Report
      2008 Annual Research Report
  • [Presentation] Field-induced quantum phase transitions in low-dimensional spin systems2009

    • Author(s)
      T. Sakai
    • Organizer
      JAEA Synchrotron Radiation Research Symposium
    • Place of Presentation
      SPring-8
    • Year and Date
      2009-03-07
    • Related Report
      2008 Annual Research Report
  • [Presentation] Quantum Phase Transition in the Spin Nanotube2009

    • Author(s)
      T. Sakai
    • Organizer
      Supercomputing in Solid State Physics
    • Place of Presentation
      柏
    • Year and Date
      2009-02-17
    • Related Report
      2008 Annual Research Report
  • [Presentation] Ring Exchange Induced Magnetic Phenomena in Spin Ladder Systems2009

    • Author(s)
      T. Sakai
    • Organizer
      International Workshop on Quantum Critical Phenomena and Novel Phases in Superclean Materials
    • Place of Presentation
      Honolulu (USA)
    • Year and Date
      2009-01-13
    • Related Report
      2008 Annual Research Report
  • [Presentation] Elementary Excitations and Dynamics of Nanowire Magnets2008

    • Author(s)
      T. Sakai
    • Organizer
      Dynamics and Manipulation of Quantum Systems
    • Place of Presentation
      東京
    • Year and Date
      2008-10-22
    • Related Report
      2008 Annual Research Report
  • [Presentation] Topics of Low-Dimensional Quantum Spin Systems2008

    • Author(s)
      T. Sakai
    • Organizer
      57th Fujihara Seminar
    • Place of Presentation
      苫小牧
    • Year and Date
      2008-07-26
    • Related Report
      2008 Annual Research Report
  • [Presentation] 歪んだダイヤモンド鎖の磁場誘起非整合秩序2008

    • Author(s)
      坂井徹
    • Organizer
      日本物理学会
    • Place of Presentation
      東京
    • Year and Date
      2008-03-27
    • Related Report
      2008 Annual Research Report
  • [Presentation] Two-step spin flop transition in quantum spin ladders2008

    • Author(s)
      T. Sakai
    • Organizer
      March Meeting of American Physical Society
    • Place of Presentation
      New Oleans
    • Year and Date
      2008-03-13
    • Related Report
      2007 Annual Research Report
  • [Presentation] Field-induced incommensurate order in quasi-1D quantum systems: Bose-Einstein condensation and possible supersolid of magnons2007

    • Author(s)
      T. Sakai
    • Organizer
      International Symposium on Physics of New Quantum Phases in Superclean Materials
    • Place of Presentation
      Gifu
    • Year and Date
      2007-11-01
    • Related Report
      2007 Annual Research Report
  • [Presentation] 3本鎖スピンチューブの磁化過程2007

    • Author(s)
      坂井徹
    • Organizer
      日本物理学会
    • Place of Presentation
      札幌
    • Year and Date
      2007-09-21
    • Related Report
      2007 Annual Research Report
  • [Presentation] Future prospects of spin tubes2007

    • Author(s)
      T. Sakai
    • Organizer
      Work Shop on Spin Tube-Recent Progresses and Future Prospects
    • Place of Presentation
      Sendai
    • Year and Date
      2007-07-24
    • Related Report
      2007 Annual Research Report
  • [Presentation] Field-induced incommensurate order in quasi-1D quantum spin systems Bose-Einstein condensation and possible supersolid of magnons2007

    • Author(s)
      T. Sakai
    • Organizer
      International Conference on Statistical Physics
    • Place of Presentation
      Genova
    • Year and Date
      2007-07-09
    • Related Report
      2007 Annual Research Report
  • [Presentation] Selection Rules for the Direct Transition of Spin Gap2007

    • Author(s)
      T. Sakai
    • Organizer
      New Developments in ESR of Strongly Correlated Systems
    • Place of Presentation
      Kashiwa
    • Year and Date
      2007-05-22
    • Related Report
      2007 Annual Research Report
  • [Presentation] Finite-temperature simulation based on the Lanczos algorithm for low-d imensional strongly correlated electron systems; high-Tc superconductors2007

    • Author(s)
      T. Sakai
    • Organizer
      Joint International Topical Meeting on Mathematics & Computations and Supercomputing in Nuclear Applications
    • Place of Presentation
      Monterey (USA)
    • Year and Date
      2007-04-18
    • Related Report
      2007 Annual Research Report
  • [Presentation] Possible field-induced supersolid in quasi-1D frustrated quantum spin systems2007

    • Author(s)
      T. Sakai
    • Organizer
      International Workshop"Physics of Supersolids and Related Topics"
    • Place of Presentation
      Yokohama
    • Year and Date
      2007-04-02
    • Related Report
      2007 Annual Research Report
  • [Remarks]

    • URL

      http://www.jaea.spring8.or.jp/cmt/

    • Related Report
      2008 Annual Research Report
  • [Remarks]

    • URL

      http://www.jaea.spring8.or.jp/cmt/

    • Related Report
      2007 Annual Research Report

URL: 

Published: 2007-04-01   Modified: 2018-03-28  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi