Experimental study of ferromagnetic superconductor using an element- and orbital-specific magnetic probe

• Project/Area Number: 25800207
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: Japan Atomic Energy Agency
• Principal Investigator: Takeda Yukiharu 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 量子ビーム応用研究センター, 主任研究員 (50399416)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2015: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2014: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2013: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
• Keywords: ウラン化合物 / 強相関電子系 / 強磁性超伝導体 / 放射光 / 軟Ｘ線 / 内殻吸収分光 / 磁気円二色性 / 内殻吸収磁気円二色性 / 超伝導 / 強磁性 / Ｘ線内殻吸収 / 軟X線磁気円二色性

Outline of Final Research Achievements

In order to improve the quality of experimental data by the soft x-ray magnetic circular dichroism (XMCD), measurement-position-observation system was newly constructed. Using the system, the XMCD measurements in ferromagnetic superconductor URhGe were done at the U 4d-5f absorption edges to extract the magnetic property at the U site. The magnetic anisotropy of the compound was investigated by applying the external magnetic field along the c-axis (magnetization easy axis) and b-axis (hard axis).
Below Curie temperature, the magnetic-field dependence of the XMCD signals shows the ferromagnetic and paramagnetic behavior for the c-axis and b-axis, respectively. From the analysis of the XMCD spectra for the c- and b-axes, it has been found that the ratio of the orbital magnetic moment to the spin magnetic moment for the c-axis is larger than that for the b-axis. These results are important information to understand the origin of the magnetic anisotropy in URhGe.

Research Products

• [Journal Article] Separation of magnetic properties at uranium and cobalt sites in UCoAl using soft x-ray magnetic circular dichroism (2013)
  • Author(s): Yukiharu Takeda, Yuji Saitoh, Tetsuo Okane, Hiroshi Yamagami, Tatsuma D. Matsuda, Etsuji Yamamoto, Yoshinori Haga, Yoshichika Onuki, and Zachary Fisk
  • Journal Title: Physical Review B Volume: 88 Issue: 7 Pages: 075108-075113
  • DOI: 10.1103/physrevb.88.075108
  • Peer Reviewed
• [Presentation] ウラン化合物強磁性超伝導体の軟X線磁気円二色性による研究 (2016)
  • Author(s): 竹田幸治, 斎藤祐児, 岡根哲夫, 山上浩志A, Jiri Pospisil, 山本悦嗣, 芳賀芳範
  • Organizer: 日本物理学会第７１回年次大会
  • Place of Presentation: 東北学院大学（宮城県仙台市）
  • Year and Date: 2016-03-19
• [Presentation] ウラン化合物のU 4d-5f共鳴光電子分光 (2016)
  • Author(s): 藤森伸一, 小畠雅明, 竹田幸治, 岡根哲夫, 斎藤祐児, 藤森淳, 山上浩志, 芳賀芳範, 山本悦嗣, 大貫惇睦
  • Organizer: 日本物理学会第７１回年次大会
  • Place of Presentation: 東北学院大学（宮城県仙台市）
  • Year and Date: 2016-03-19
• [Presentation] BL23SUにおける軟Ｘ線磁気円二色性装置の紹介 (2016)
  • Author(s): 竹田幸治
  • Organizer: 第一回SPring-8先端利用技術ワークショップ
  • Place of Presentation: グランパークプラザ（東京都港区）
  • Year and Date: 2016-03-11
  • Invited
• [Presentation] Evolution of ferromagnetism in Ru doped UCoGe studied by PND and XMCD (2015)
  • Author(s): Jiri Pospisil，Michal Valiska，Anne Stunault，Yukiharu Takeda，Beatrice Gillon，Yoshinori Haga，Karel Prokes，Mohsen M. Abd-Elmeguid，Gwilherm Nenert，Laurent Chapon，Arsene Goukasov，Etsuji Yamamoto and Vladimir Sechovsky
  • Organizer: 日本物理学会 第７０回年次大会
  • Place of Presentation: 早稲田大学 (東京都新宿区)
  • Year and Date: 2015-03-21 – 2015-03-24
• [Presentation] 軟X線磁気円二色性によるUCoAlの元素選択的磁化測定 (2014)
  • Author(s): 竹田幸治、斎藤祐児、岡根哲夫、山上浩志、松田達磨、山本悦嗣、芳賀芳範、大貫惇睦、Zachary Fisk
  • Organizer: 第27回日本放射光学会年会・放射光科学合同シンポジウム
  • Place of Presentation: 広島市
• [Presentation] 軟X線磁気円二色性によるUCoAlの元素選択的磁化測定 (2014)
  • Author(s): 竹田幸治、斎藤祐児、岡根哲夫、山上浩志、松田達磨、山本悦嗣、芳賀芳範、大貫惇睦、Zachary Fisk
  • Organizer: 日本物理学会第69回年次大会
  • Place of Presentation: 平塚市