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Physics of odd-frequency Cooper pairs in multi-band/orbital superconductors.

Research Project

Project/Area Number 20H01857
Research Category

Grant-in-Aid for Scientific Research (B)

Allocation TypeSingle-year Grants
Section一般
Review Section Basic Section 13030:Magnetism, superconductivity and strongly correlated systems-related
Research InstitutionHokkaido University

Principal Investigator

Asano Yasuhiro  北海道大学, 工学研究院, 准教授 (20271637)

Co-Investigator(Kenkyū-buntansha) 田仲 由喜夫  名古屋大学, 工学研究科, 教授 (40212039)
水島 健  大阪大学, 大学院基礎工学研究科, 准教授 (50379707)
Project Period (FY) 2020-04-01 – 2023-03-31
Project Status Completed (Fiscal Year 2022)
Budget Amount *help
¥18,070,000 (Direct Cost: ¥13,900,000、Indirect Cost: ¥4,170,000)
Fiscal Year 2022: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
Fiscal Year 2021: ¥7,020,000 (Direct Cost: ¥5,400,000、Indirect Cost: ¥1,620,000)
Fiscal Year 2020: ¥8,840,000 (Direct Cost: ¥6,800,000、Indirect Cost: ¥2,040,000)
Keywords超伝導
Outline of Research at the Start

物質表面や接合界面の存在、あるいは様々なポテンシャルのために超伝導凝縮体が変型を受けたときに現れるのが奇周波数電子対である。超伝導現象は平均場理論によってうまく記述できており、奇周波数電子対はその基礎方程式の解の一部をなしている。解の数学的記述には不可欠である一方、奇周波数電子対は、その性質や超伝導現象において担う役割に関して不明な点が多い。本研究の目的は、軌道や谷など電子系に自由度の多い超伝導体、トポロジカルに非自明な超伝導体の磁束芯、スピン軌道相互作用の強い銅酸化物超伝導薄膜の接合、において現れる奇周波数電子対の性質を明らかにすることである。。

Outline of Final Research Achievements

The purpose of this project is to make clear roles of odd-frequency Cooper pairs on characteristic physical phenomena of in superconductors. Our research findings are as follows. Quasiparticles on the Bogoliubov-Fermi surface always accompany odd-frequency Cooper pairs. The magnetic susceptibility has off-diagonal elements when pseudospin-quintet states of a j=3/2 superconductor is characterized by an s-wave pair potential. Many Hamiltonians for two-band/orbital superconductivity and j=3/2 superconductivity describe unstable superconducting phases. The instability is derived from the existence of odd-frequency pairs in the bulk. Moreover, the anomalous proximity effect is not a unique property to spin-triplet superconductors but a common property of superconductors characterized by nonzero Atiyah-Singer indices.

Academic Significance and Societal Importance of the Research Achievements

本研究で対象とした多自由度超伝導は、トポロジカルに非自明な絶縁相や半金属相を土台に発現していると考えられており、新しいクラスの超伝導だと認識され始めている。既存の超伝導と何が質的に違うのかを明らかにすることは、トポロジカル物質の物理学の重要課題の一つであると言える。
最近多自由度超伝導を表現する理論模型が調べられ始めているが、その特徴は多くの物質パラメータを含むことである。我々は、それらの模型の多くが熱力学的に不安定な超伝導相を記述していることを明らかにした。逆に言えば、実際の伝導体で発現する安定な超伝導を記述する模型が満たすべき条件を明らかにし解析の出発点を定めたことになる。

Report

(4 results)
  • 2022 Annual Research Report   Final Research Report ( PDF )
  • 2021 Annual Research Report
  • 2020 Annual Research Report
  • Research Products

    (24 results)

All 2023 2022 2021 2020 Other

All Int'l Joint Research (1 results) Journal Article (16 results) (of which Int'l Joint Research: 6 results,  Peer Reviewed: 16 results,  Open Access: 4 results) Presentation (6 results) (of which Int'l Joint Research: 4 results,  Invited: 1 results) Book (1 results)

  • [Int'l Joint Research] Max Planck INstitute(ドイツ)

    • Related Report
      2021 Annual Research Report
  • [Journal Article] Nuclear spin relaxation rate of nonunitary Dirac and Weyl superconductors2023

    • Author(s)
      Maeno Koki、Kawaguchi Yuki、Asano Yasuhiro、Kobayashi Shingo
    • Journal Title

      Physical Review B

      Volume: 107 Issue: 6 Pages: 064511-064511

    • DOI

      10.1103/physrevb.107.064511

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Spin Susceptibility of a J= 3/2 Superconductor2023

    • Author(s)
      Kim Dakyeong、Sato Takumi、Kobayashi Shingo、Asano Yasuhiro
    • Journal Title

      Journal of the Physical Society of Japan

      Volume: 92 Issue: 5

    • DOI

      10.7566/jpsj.92.054703

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Odd-frequency Cooper pair around a magnetic impurity2022

    • Author(s)
      Suzuki Shu-Ichiro、Sato Takumi、Asano Yasuhiro
    • Journal Title

      Physical Review B

      Volume: 106 Issue: 10

    • DOI

      10.1103/physrevb.106.104518

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Odd-parity pairing correlations in a d-wave superconductor2021

    • Author(s)
      Lee Jaechul、Ikegaya Satoshi、Asano Yasuhiro
    • Journal Title

      Physical Review B

      Volume: 103 Issue: 10

    • DOI

      10.1103/physrevb.103.104509

    • NAID

      120007044499

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Josephson effect of superconductors with J=3/2 electrons2021

    • Author(s)
      Kim Dakyeong、Kobayashi Shingo、Asano Yasuhiro
    • Journal Title

      Physical Review B

      Volume: 103 Issue: 18

    • DOI

      10.1103/physrevb.103.184516

    • NAID

      120007089512

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Strong anomalous proximity effect from spin-singlet superconductors2021

    • Author(s)
      Satoshi Ikegaya, Jaechul Lee, Andreas P. Schnyder, Yasuhiro Asano
    • Journal Title

      Physical Review B

      Volume: 104 Issue: 2

    • DOI

      10.1103/physrevb.104.l020502

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Quasiparticle on Bogoliubov Fermi Surface and Odd-Frequency Cooper Pair2021

    • Author(s)
      Kim Dakyeong、Kobayashi Shingo、Asano Yasuhiro
    • Journal Title

      Journal of the Physical Society of Japan

      Volume: 90 Issue: 10 Pages: 104708-104708

    • DOI

      10.7566/jpsj.90.104708

    • NAID

      40022709394

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Generalization of spectral bulk-boundary correspondence2021

    • Author(s)
      Tamura Shun、Hoshino Shintaro、Tanaka Yukio
    • Journal Title

      Physical Review B

      Volume: 104 Issue: 16 Pages: 165125-165125

    • DOI

      10.1103/physrevb.104.165125

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Anomalous inverse proximity effect in unconventional superconductor junctions2021

    • Author(s)
      Suzuki Shu-Ichiro、Hirai Takashi、Eschrig Matthias、Tanaka Yukio
    • Journal Title

      Physical Review Research

      Volume: 3 Issue: 4 Pages: 0431481-12

    • DOI

      10.1103/physrevresearch.3.043148

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Spin-polarized phases of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>P</mml:mi><mml:mn>2</mml:mn><mml:none /><mml:mprescripts /><mml:none /><mml:mn>3</mml:mn></mml:mmultiscripts></mml:math> superfluids in neutron stars2021

    • Author(s)
      Mizushima Takeshi、Yasui Shigehiro、Inotani Daisuke、Nitta Muneto
    • Journal Title

      Physical Review C

      Volume: 104 Issue: 4

    • DOI

      10.1103/physrevc.104.045803

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Josephson effect in two-band superconductors2020

    • Author(s)
      A. Sasaki, S. Ikegaya, T. Habe, A. A. Golubov, and Y. Asanp
    • Journal Title

      Physical Review B

      Volume: 101 Issue: 18

    • DOI

      10.1103/physrevb.101.184501

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Nodal Andreev spectra in multi-Majorana three-terminal Josephson junctions2020

    • Author(s)
      Sakurai Keimei、Mercaldo Maria Teresa、Kobayashi Shingo、Yamakage Ai、Ikegaya Satoshi、Habe Tetsuro、Kotetes Panagiotis、Cuoco Mario、Asano Yasuhiro
    • Journal Title

      Physical Review B

      Volume: 101 Issue: 17

    • DOI

      10.1103/physrevb.101.174506

    • NAID

      120006863173

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Identification of spin-triplet superconductivity through a helical-chiral phase transition in Sr2RuO4 thin films2020

    • Author(s)
      Ikegaya S.、Yada K.、Tanaka Y.、Kashiwaya S.、Asano Y.、Manske D.
    • Journal Title

      Physical Review B

      Volume: 101 Issue: 22 Pages: 220501-220501

    • DOI

      10.1103/physrevb.101.220501

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Superconductivity in Cu-doped Bi2Se3 with potential disorder2020

    • Author(s)
      Sato Takumi、Asano Yasuhiro
    • Journal Title

      Physical Review B

      Volume: 102 Issue: 2

    • DOI

      10.1103/physrevb.102.024516

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Critical end point and universality class of neutron 3P2 superfluids in neutron stars2020

    • Author(s)
      Mizushima Takeshi、Yasui Shigehiro、Nitta Muneto
    • Journal Title

      Physical Review Research

      Volume: 2 Issue: 1 Pages: 013194-013194

    • DOI

      10.1103/physrevresearch.2.013194

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] Orbital tunable 0?π transitions in Josephson junctions with noncentrosymmetric topological superconductors2020

    • Author(s)
      Fukaya Yuri、Yada Keiji、Tanaka Yukio、Gentile Paola、Cuoco Mario
    • Journal Title

      Physical Review B

      Volume: 102 Issue: 14 Pages: 144512-144512

    • DOI

      10.1103/physrevb.102.144512

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Presentation] ボゴリューボフ・フェルミ面をもつ超伝導体における準粒子状態密度2023

    • Author(s)
      佐藤匠, 小林伸吾, 浅野泰寛
    • Organizer
      日本物理学会 2023年春季大会
    • Related Report
      2022 Annual Research Report
  • [Presentation] Quasiparticle density of states in a superconductor with Bogoliubov Fermi Surfaces2022

    • Author(s)
      Takumi Sato, Shingo Kobayashi, and Yasuhiro Asano
    • Organizer
      Oxide Superspin 2022
    • Related Report
      2022 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Odd-frequency Cooper pairing correlations around magnetic impurities2022

    • Author(s)
      Shu-Ichiro Suzuki, Takumi Sato, and Yasuhiro Asano
    • Organizer
      29th International Conference on Low Temperature Physics
    • Related Report
      2022 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Odd-parity pairing correlations in a d-wave superconductor2021

    • Author(s)
      浅野泰寛
    • Organizer
      日本物理学会
    • Related Report
      2021 Annual Research Report
  • [Presentation] Superconductivity in Cu-doped Bi2Se3 with potential disorder2021

    • Author(s)
      Takumi Sato
    • Organizer
      Oxide Superspin 2021
    • Related Report
      2021 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Josephson Effect of two-band/orbital superconductors2021

    • Author(s)
      Y. Asano
    • Organizer
      Topological Superconductivity in Quantum Materials
    • Related Report
      2020 Annual Research Report
    • Int'l Joint Research / Invited
  • [Book] Andreev Reflection in Superconducting Junctions2021

    • Author(s)
      Yasuhiro Asano
    • Total Pages
      132
    • Publisher
      Springer
    • ISBN
      9789811641657
    • Related Report
      2021 Annual Research Report

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Published: 2020-04-28   Modified: 2024-01-30  

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