Elucidation of gap structure and enhancement of critical current density in iron-based superconductors by swift-particle irradiations

2018 Fiscal Year Annual Research Report

• Project/Area Number: 17H01141
• Research Institution: The University of Tokyo
• Principal Investigator: 為ケ井 強 東京大学, 大学院工学系研究科(工学部), 准教授 (30183073)
• Co-Investigator(Kenkyū-buntansha): 岡安 悟 国立研究開発法人日本原子力研究開発機構, 原子力科学研究部門 原子力科学研究所 先端基礎研究センター, 研究主幹 (50354824) ; 一瀬 中 一般財団法人電力中央研究所, 電力技術研究所, 上席研究員 (70371284)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Keywords: 鉄系超伝導体 / 粒子線照射 / 臨界電流密度 / 超伝導ギャップ構造

Outline of Annual Research Achievements

鉄系超伝導体を対象として、主にプロトンや重イオン等の高エネルギー粒子線照射により生成される欠陥を用いて、基礎面では超伝導発現機構に関連する超伝導ギャップ構造の解明を、応用面では臨界電流密度の増強を目指して研究を行い、以下の成果を得た。
１、プロトン照射したFeSeにおけるTcの特異な照射量依存性の発見。２、重イオン照射した(Ba,K)Fe2As2における磁場侵入長の測定結果がs±波超伝導による説明。３、FeSeにおける角度依存比熱測定による異方的な複数のギャップの存在の確認。４、スプレー状に柱状欠陥を導入した(Ba,K)Fe2As2における特異な臨界電流密度の増強の発見。５、EuFe2(As,P)2における超伝導と強磁性の共存状態の詳細解明。６、(Ba,K)Fe2As2丸型線材における大きな臨界電流密度の実現（38 kA/cm2, 4.2 K, 10 T）。７、BaFe2(As,P)2におけるプロトン照射効果の解明。８、CaKFe4As4単結晶における異方的臨界電流の解明。９、CaKFe4As4丸型線材の作製と臨界電流密度の評価。１０、従来型超伝導体NbSe2における粒子線照射による臨界電流密度増大の確認。

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

11系および122系の鉄系超伝導体への粒子線照射効果をさらに解明するとともに、新たな構造を持つ鉄系超伝導体の磁束状態の解明および線材の作製を行えたと共に、従来型超伝導体における粒子線照射効果の研究に着手できたため。

Strategy for Future Research Activity

引き続き、粒子線照射による散乱体導入効果の検討によるギャップ構造の解明を他の鉄系超伝導体で継続するとともに、新たな鉄系超伝導体にける点状および柱状欠陥による増強されたピン止め機構を解明する。さらに、より実用的で大きな臨界電流密度を持つ丸型線材の開発を行う。さらに、各種従来型超伝導体における粒子線照射効果を詳細に検討する。

Research Products

• [Int'l Joint Research] Politecnico di Torino(イタリア)
  • Country Name: ITALY
  • Counterpart Institution: Politecnico di Torino
• [Int'l Joint Research] Southeast University/IOP(中国)
  • Country Name: CHINA
  • Counterpart Institution: Southeast University/IOP
• [Int'l Joint Research] National Institute of Materials Physics(ルーマニア)
  • Country Name: ROMANIA
  • Counterpart Institution: National Institute of Materials Physics
• [Journal Article] Recent Progress of Iron Based Superconducting Round Wires (2019)
  • Author(s): S. Pyon, T. Tamegai, K. Takano, H. Kajitani, N. Koizumi, and S. Awaji
  • Journal Title: J. Phys.: Conf. Ser. Volume: 1293 Pages: 012042_1-10
  • DOI: 10.1088/1742-6596/1293/1/012042
  • Peer Reviewed / Open Access
• [Journal Article] Fabrication of (Ba,Na)Fe2As2 Round Wires using HIP Process (2019)
  • Author(s): D. Miyawaki, S. Pyon, T. Tamegai, S. Awaji, K. Takano, H. Kajitani, and N. Koizumi
  • Journal Title: J. Phys.: Conf. Ser. Volume: 1293 Pages: 012043_1-7
  • DOI: 10.1088/1742-6596/1293/1/012043
  • Peer Reviewed / Open Access
• [Journal Article] Multiple topological states in iron-based superconductors (2019)
  • Author(s): P. Zhang, Z. J. Wang, X. X. Wu, K. Yaji, Y. Ishida, Y. Kohama, G. Y. Dai, Y. Sun, C. Bareille, K. Kuroda, T. Kondo, K. Okazaki, K. Kindo, X. C. Wang, C. Q. Jin, J. P. Hu, R. Thomale, K. Sumida, S. L. Wu, K. Miyamoto, T. Okuda, H. Ding, G. Gu, T. Tamegai, T. Kawakami, M. Sato, and S. Shin
  • Journal Title: Nature Physics Volume: 15 Pages: 41-47
  • DOI: 10.1038/s41567-018-0280-z
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Deviation from canonical collective creep behavior in Li0.8Fe0.2OHFeSe (2019)
  • Author(s): Yue Sun, Sunseng Pyon, Run Yang, Xianggang Qiu, Jiajia Feng, Zhixiang Shi, and Tsuyoshi Tamegai
  • Journal Title: Journal of Physical Society of Japan Volume: 88 Pages: 034703_1-5
  • DOI: 10.7566/JPSJ.88.034703
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Large and significantly anisotropic critical current density induced by planar defects in CaKFe4As4 single crystals (2019)
  • Author(s): Sunseng Pyon, Ayumu Takahashi, Ivan Veshchunov, Tsuyoshi Tamegai, Shigeyuki Ishida, Akira Iyo, Hiroshi Eisaki, Motoharu Imai, Hideki Abe, Taichi Terashima, Ataru Ichinose
  • Journal Title: Physical Review B Volume: 99 Pages: 104506_1-8
  • DOI: 10.1103/PhysRevB.99.104506
  • Peer Reviewed
• [Journal Article] Demonstration of excellent Jc performance in (AE,Na)Fe2As2 (AE: Sr, Ba) PIT wires (2019)
  • Author(s): T. Tamegai, T. Suwa, D. Miyawaki, S. Pyon, K. Takano, H. Kajitani, N. Koizumi, and S. Awaji
  • Journal Title: IEEE Trans. Appl. Supercond. Volume: 29 Pages: 7300605_1-5
  • DOI: 10.1109/TASC.2019.2905159
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Effects of Swift-Particle Irradiations on Critical Current Density in CaKFe4As4 (2019)
  • Author(s): A. Takahashi, S. Pyon, S. Okayasu, S. Ishida, A. Iyo, H. Eisaki, M. Imai, H. Abe, T. Terashima and T. Tamegai
  • Journal Title: J. Phys.: Conf. Ser. Volume: 印刷中 Pages: 印刷中
  • Peer Reviewed
• [Journal Article] Promising characteristics in Ag-sheathed (Sr,Na)Fe2As2tape (2018)
  • Author(s): Takahiro Suwa, Sunseng Pyon, TsuyoshiTamegai, and Satoshi Awaji,
  • Journal Title: Applied Physics Express Volume: 11 Pages: 063101_1-5
  • DOI: 10.7567/APEX.11.063101
  • Peer Reviewed
• [Journal Article] Disorder-sensitive node-like small gap in FeSe (2018)
  • Author(s): Yue Sun, Shunichiro Kittaka, Shota Nakamura, Toshiro Sakakibara, Peng Zhang, Shik Shin, Koki Irie, Takuya Nomoto, Kazushige Machida, Jingting Chen, and Tsuyoshi Tamegai
  • Journal Title: Physical Review B Volume: 98 Pages: 064505_1-7
  • DOI: 10.1103/PhysRevB.98.064505
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] AC magnetic response of superconducting single crystals exhibiting a second peak on the DC magnetization curves (2018)
  • Author(s): L. Miu, A. Ionescu, A. Crisan, D. Miu, T. Petrisor, A. Park, and T. Tamegai
  • Journal Title: Physica C Volume: 555 Pages: 1-6
  • DOI: 10.1016/j.physc.2018.10.002
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Fabrications and Characterizations of CaKFe4As4 Round Wires Sintered at High Pressure (2018)
  • Author(s): Sunseng Pyon, Daisuke Miyawaki, Ivan Veshchunov, Tsuyoshi Tamegai, Katsutoshi Takano, Hideki Kajitani, Norikiyo Koizumi, and Satoshi Awaji
  • Journal Title: Applied Physics Express Volume: 11 Pages: 123101_1-5
  • DOI: 10.7567/APEX.11.123101
  • Peer Reviewed
• [Journal Article] Fabrication Process and Pressure Dependence of Critical Current Density in Ba1-xKxFe2As2 Superconducting HIP Wires (2018)
  • Author(s): Sunseng Pyon, Takahiro Suwa, Tsuyoshi Tamegai, Katsutoshi Takano, Hideki Kajitani, Norikiyo Koizumi, Satoshi Awaji
  • Journal Title: J. Phys.: Conf. Ser. Volume: 1054 Pages: 012044_1-6
  • DOI: 10.1088/1742-6596/1054/1/012044
  • Peer Reviewed
• [Journal Article] Anisotropy of Critical Current Densities in Ba1-xKxFe2As2 and Ba(Fe1-xCox)2As2 with Splayed Columnar Defects (2018)
  • Author(s): N. Ito, S. Pyon, T. Kambara, A. Yoshida, S. Okayasu, A. Ichinose, T. Tamegai
  • Journal Title: J. Phys.: Conf. Ser. Volume: 1054 Pages: 012020_1-6
  • DOI: 10.1088/1742-6596/1054/1/012020
  • Peer Reviewed
• [Journal Article] Enhancement of Critical Current Density in AgSn-sheathed (Sr,Na)Fe2As2 Superconducting Tapes (2018)
  • Author(s): T. Suwa, S. Pyon, T. Tamegai, S. Awaji
  • Journal Title: J. Phys.: Conf. Ser. Volume: 1054 Pages: 012045_1-5
  • DOI: 10.1088/1742-6596/1054/1/012045
  • Peer Reviewed
• [Presentation] CaKFe4As4における 異方的臨界電流密度 (2019)
  • Author(s): 為ヶ井 強、卞 舜生、高橋歩夢、小林優斗、岡安 悟、一瀬 中
  • Organizer: つくば-柏-本郷 超伝導かけはしプロジェクト ワークショップ
• [Presentation] Enhancement of Critical Current Density at Some Fraction of BΦ in Superconductors with Splayed Columnar Defects (2019)
  • Author(s): T. Tamegai, Wenjie Li, A. Takahashi, S. Pyon, S. Okayasu, A. Ichinose
  • Organizer: Plasma 2019
  • Int'l Joint Research / Invited
• [Presentation] Enhancement of Jc at around 1/3BΦ in Iron-based Superconductors with Splayed Columnar Defects (2019)
  • Author(s): T. Tamegai, A. Takahashi, N. Ito, S. Pyon, A. Yoshida, T. Kambara, S. Okayasu, A. Ichinose
  • Organizer: APS March Meeting
  • Int'l Joint Research
• [Presentation] Fragile zero-energy vortex bound state in the topological superconductor candidate FeTe0.6Se0.4 (2019)
  • Author(s): T. Machida, Y. Sun, S. Pyon, S. Takeda, Y. Kohsaka, T. Hanaguri, T. Sasagawa, T. Tamegai
  • Organizer: APS March Meeting
  • Int'l Joint Research
• [Presentation] Superconducting and normal state anisotropy of Fe(Te,Se) single crystals (2019)
  • Author(s): Y. Sun, H. Ohnuma, N. Mine, H. Kitano, and T. Tamegai
  • Organizer: 日本物理学会年会
• [Presentation] Anisotropic critical current density in NbSe2 with splayed columnar defects (2019)
  • Author(s): W. Li, T. Tamegai, S. Pyon, I. Veshchunov, A. Takahashi, D. Miyawaki, and S. Okayasu
  • Organizer: 日本物理学会年会
• [Presentation] Fe(Se,Te)単結晶の面内微小接合素子の作製と電気化学的キャリア制御 (2019)
  • Author(s): 大沼遥, 岡田一宏, 高木友宏, 野地尚, 小池洋二, 鮎川晋也, 為ヶ井強, 孫悦, 北野晴久
  • Organizer: 日本物理学会年会
• [Presentation] Ba1-xNaxFe2As2丸型HIP線゛の作製条件の最適化と性能の向上 (2019)
  • Author(s): 宮脇大輔, 卞舜生, 為ヶ井強, 淡路智
  • Organizer: 日本物理学会年会
• [Presentation] 122型鉄系超伝導体に対するc軸非対称なスプレイド柱状欠陥の効果 (2019)
  • Author(s): 高橋歩夢, 卞舜生, 神原正A, 吉田敦A, 岡安悟B, 為ヶ井強
  • Organizer: 日本物理学会年会
• [Presentation] CaKFe4As4多結晶の熱処理純良化と超伝導線材の臨界電流密度向上 (2019)
  • Author(s): 卞舜生, 宮脇大輔, 為ヶ井強, 淡路智
  • Organizer: 日本物理学会年会
• [Presentation] In-plane Anisotropy of Critical Current Density in Superconductors with Splayed Columnar Defects (2018)
  • Author(s): T. Tamegai, A. Park, N. Ito, A. Takahashi, S. Pyon, T. Nishizaiki, T. Kambara, A. Yoshida, S. Okayasu, A. Ichinose
  • Organizer: ICSM2018
  • Int'l Joint Research / Invited
• [Presentation] Anomalous Enhancement of Critical Current Density in Iron-based Superconductors with Splayed Columnar Defects (2018)
  • Author(s): T. Tamegai, A. Park, N. Ito, A. Yamaoka, S. Pyon, T. Kambara, A. Yoshida, S. Okayasu, A. Ichinose
  • Organizer: 8th International Conference -Science and Engineering of Novel Superconductors
  • Int'l Joint Research / Invited
• [Presentation] 新規超伝導マグネットの開発と 強磁場発生 (2018)
  • Author(s): 為ヶ井強
  • Organizer: 超伝導とその周辺：渦糸物理と検出器の新展開
• [Presentation] Anomalous Enhancement of Critical Current Density due to Novel Planar Defects in CaKFe4As4 (2018)
  • Author(s): T. Tamegai, A. Takahashi, S. Pyon, N. Ito, S. Ishida, A. Iyo, H. Eisaki, M. Imai, H. Abe, T. Terashima, S. Ooi, A. Ichinose
  • Organizer: M2S2018
  • Int'l Joint Research
• [Presentation] Effects of Ion-irradiation on critical current density in CaKFe4As4 single crystals (2018)
  • Author(s): S. Pyon, A. Tahakashi, I. Veshchunov, N. Ito, T. Tamegai, S. Ishida, A. Iyo, H. Eisaki, M. Imai, H. Abe, T. Terashima
  • Organizer: M2S2018
  • Int'l Joint Research
• [Presentation] Comparison of 1.19 GeV Pb and 320 MeV Au Irradiation Effects on Critical Current Density in Ba0.6K0.4 Fe2As2 (2018)
  • Author(s): A. Takahashi, S. Pyon, S. Okayasu, G. Ghigo, D. Torsello, R. Gerbaldo, T. Tamegai
  • Organizer: M2S2018
  • Int'l Joint Research
• [Presentation] Ultra-Low Temperature Spectroscopic Imaging Studies of Vortices in the Topological Superconductor FeTe0.6Se0.4 (2018)
  • Author(s): T. Machida, Y. Sun, S. Takeda, Y. Kohsaka, T. Hanaguri, T. Sasagawa, T. Tamegai
  • Organizer: M2S2018
  • Int'l Joint Research
• [Presentation] Developments of Round Wires of Iron-based Superconductors (2018)
  • Author(s): T. Tamegai, S. Pyon, T. Suwa, D. Miyawaki, H. Kajitani, N. Koizumi, S. Awaji
  • Organizer: International Workshop on Superconducting Materials for Applications
  • Int'l Joint Research
• [Presentation] トポロジカル超伝導体候補物質FeTe0.6Se0.4における渦糸芯電子状態の走査型トンネル分光 (2018)
  • Author(s): 町田理, 孫悦, 竹田駿, 幸坂祐生, 花栗哲郎, 笹川崇男, 為ヶ井強
  • Organizer: 日本物理学会秋季大会
• [Presentation] 122型鉄系超伝導体の臨界電流密度に対する1.19 GeV Pb照射効果 (2018)
  • Author(s): 高橋歩夢, 卞舜生, G. Ghigo, D. Torsello, R. Gerbaldo, 為ヶ井強
  • Organizer: 日本物理学会秋季大会
• [Presentation] (Ba,Na)Fe2As2丸型HIP線材の作製と臨界電流密度の向上 (2018)
  • Author(s): 宮脇大輔, 為ヶ井強, 卞舜生, 淡路智
  • Organizer: 日本物理学会秋季大会
• [Presentation] 超伝導体における量子磁束運動の抑制 (2018)
  • Author(s): 為ヶ井強
  • Organizer: 日本物理学会秋季大会
• [Presentation] CaKFe4As4超伝導体線材の作製と臨界電流密度の評価 (2018)
  • Author(s): 卞舜生, 宮脇大輔, 為ヶ井強, 淡路智
  • Organizer: 日本物理学会秋季大会
• [Presentation] Quasi-particle evidence for the nematic state above superconductivity in Sr0.1Bi2Se3 (2018)
  • Author(s): Yue Sun, S. Kittaka, T. Sakakibara, K. Machida, T. Tamegai, J. Wang, J. Wen
  • Organizer: 日本物理学会秋季大会
• [Presentation] Demonstration of Excellent Jc Characteristics in (AE,Na)Fe2As2 (AE: Sr, Ba) PIT Wires (2018)
  • Author(s): T. Tamegai, T. Suwa, D. Miyawaki, S. Pyon, K. Takano, H. Kajitani, N. Koizumi, S. Awaji
  • Organizer: Applied Superconductivity Conference 2018
  • Int'l Joint Research
• [Presentation] スプレー柱状欠陥を導入した NbSe2における磁束状態 (2018)
  • Author(s): T. Tamegai, Wenjie Li, S. Pyon, S. Okayasu, A. Ichinose
  • Organizer: 第26回渦糸物理国内会議
• [Presentation] 超伝導線材の臨界電流密度 (2018)
  • Author(s): 卞 舜生
  • Organizer: 第26回渦糸物理国内会議
• [Presentation] Evaluation of Anisotropic Critical Current Density in CaKFe4As4 (2018)
  • Author(s): T. Tamegai, A. Tahakashi, S. Pyon, I. Veshchunov, S. Ishida, A. Iyo, H. Eisaki, M. Imai, H. Abe, T. Terashima, S. Ooi, and A. Ichinose
  • Organizer: ISS2018
  • Int'l Joint Research
• [Presentation] Recent Progress of Iron Based Superconducting Round Wires (2018)
  • Author(s): Sunseng Pyon, Tsuyoshi Tamegai, Katsutoshi Takano, Hideki Kajitani, Norikiyo Koizumi, Satoshi Awaji
  • Organizer: ISS2018
  • Int'l Joint Research / Invited
• [Presentation] Effects of Swift-Particle Irradiations on Critical Current Density in CaKFe4As4 (2018)
  • Author(s): A. Takahashi, S. Pyon, S. Okayasu, S. Ishida, A. Iyo, H. Eisaki, M. Imai, H. Abe, T. Terashima T. Tamegai
  • Organizer: ISS2018
  • Int'l Joint Research
• [Presentation] Fabrication of (Ba,Na)Fe2As2 round wires using HIP process (2018)
  • Author(s): D. Miyawaki, S. Pyon, T. Tamegai, S. Awaji, K. Takano, H. Kajitani, and N. Koizumi
  • Organizer: ISS2018
  • Int'l Joint Research