Antisymmetric spin-orbit coupling effect in Kondo semiconductors with zigzag chains

• Project Area: J-Physics: Physics of conductive multipole systems
• Project/Area Number: 16H01076
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: Hiroshima University
• Principal Investigator: 高畠 敏郎 広島大学, 先端物質科学研究科, 教授 (40171540)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥6,500,000 (Direct Cost: ¥5,000,000、Indirect Cost: ¥1,500,000); Fiscal Year 2017: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000); Fiscal Year 2016: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000)
• Keywords: 強相関電子系 / 近藤半導体 / セリウム化合物 / ジグザグ鎖 / 反対称スピン軌道相互作用 / 電荷励起ギャップ / 物性実験 / スピン軌道相互作用 / トンネル分光

Outline of Annual Research Achievements

直方晶の近藤半導体CeOs2Al10では，Ce原子サイトは局所対称性を持たず，c軸方向にジグザグ鎖構造をなしている。Ce化合物としては例外的に高いTN=28.5 Kで反強磁性秩序し，その際Ce磁気モーメントは磁気困難軸であるｃ軸方向に向く。この特異な反強磁性秩序の原因を探るために，本研究では，その混成ギャップ形成と特異な反強磁性秩序における反対称スピン・軌道交互作用の効果を調べることを目的とし，本年度に計画した研究を行い下記の成果を得た。
高畠は連携研究者の梅尾及び大学院生とともにCe（Ru1-xOsx）2Al10 単結晶を育成し，その電気抵抗，磁化，比熱を常圧と一軸圧下で測定した。その結果，近藤温度TKとエネルギーギャップはxに比例して増加したが，TNはｘ = 0.71で最高となった。ｘの全ての範囲で，単結晶のｂ軸方向に加圧すると，TKは変化しないのにTNが著しく上昇することを確かめた。これらの結果は，TNを高めている機構が，異方的なc-f混成に加えて，ｂ軸方向の電荷輸送に関係していることを意味している。この結果は，連携研究者の木村が偏光反射分光によって提案したモデル，すなわち，b軸方向の電荷励起ギャップ形成が反強磁性を引き起こすという説を支持している。
浴野（連携研究者）は大学院生とともにCeOs2Al10単結晶の走査トンネル顕微/分光実験を実施し，TN以下の温度で50meVの反強磁性ギャップが現れることを観測し，先に行った破断接合実験の結果を確認した。研究協力者A. Severing はCeOs2Al10に5d電子・正孔をドープした系の直線・円偏向X線吸収分光によって，磁気モーメントの大きさとその向きは，a軸方向のc-f混成強度に依存していることを明らかにした。連携研究者の横谷は軟X線角度分解光電子分光実験でフェルミ面の一部を観測することに成功した。

Research Progress Status

29年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

29年度が最終年度であるため、記入しない。

Research Products

• [Int'l Joint Research] Rutherford Appleton Laboratory/Durham University(英国)
• [Int'l Joint Research] Wien University(Austria)
• [Int'l Joint Research] University of Cologne/Max Planck ICPS/University of Augsburg(Germany)
• [Int'l Joint Research] Synchrotron SOLEIL(France)
• [Int'l Joint Research] Rutherford Appleton Laboratory/Durham University/University College London(英国)
• [Int'l Joint Research] TU Wien(Austria)
• [Int'l Joint Research] Max Planck Institute(Germany)
• [Journal Article] A spin-canted antiferromagnetic ground state in CeRu2Al10 (2018)
  • Author(s): P. Dean, Y. Muro, T. Takabatake, P.D. Hatton
  • Journal Title: J. Phys. Soc. Jpn. Volume: 87
  • NAID: 210000134656
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Tuning the hybridization and magnetic ground state of electron and hole doped CeOs2Al10: an x-ray spectroscopy study (2018)
  • Author(s): K. Chen, M. Sundermann, F. Strigari, J. Kawabata, T. Takabatake, A. Tanaka, P. Bencok, F. Choueikani, A. Severing
  • Journal Title: Phys. Rev. B Volume: 97 Issue: 15
  • DOI: 10.1103/physrevb.97.155106
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Different variations of Néel temperature TN and Kondo temperature TK in the alloy system Ce(Ru1-xOsx)2Al10 under uniaxial pressure (2018)
  • Author(s): T. Takeuchi, K. Hayashi, K. Umeo, T. Takabatake
  • Journal Title: J. Phys. Soc. Jpn. Volume: 87 Issue: 5 Pages: 054702-054702
  • DOI: 10.7566/jpsj.87.054702
  • NAID: 210000134820
  • Peer Reviewed
• [Journal Article] Quantum criticality and development of antiferromagnetic order in the quasikagome Kondo lattice CeRh1-xPdxSn (2017)
  • Author(s): C. L. Yang, S. Tsuda, K. Umeo, Y. Yamane, T. Onimaru, T. Takabatake, N. Kikugawa, T. Terashima, S. Uji
  • Journal Title: Phys. Rev. B Volume: 96 Issue: 4
  • DOI: 10.1103/physrevb.96.045139
  • Peer Reviewed
• [Journal Article] Uniaxial stress tuning of geometrical frustration in a Kondo lattice (2017)
  • Author(s): R. Kuechler, C. Stingl, Y. Tokiwa, M. S. Kim, T. Takabatake, P. Gegenwart
  • Journal Title: Phys. Rev. B Volume: 96 Issue: 24
  • DOI: 10.1103/physrevb.96.241110
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Anisotropic dependence of the magnetic transition on uniaxial pressure in the Kondo semiconductors CeT2Al10 (T = Ru and Os) (2017)
  • Author(s): K. Hayashi, K. Umeo, T. Takeuchi, J. Kawabata, Y. Muro, T. Takabatake
  • Journal Title: Phys. Rev. B Volume: 96 Issue: 24
  • DOI: 10.1103/physrevb.96.245130
  • Peer Reviewed
• [Journal Article] Structural and magnetic properties of a novel ternary intermetallic compound CePd3Sn2 (2017)
  • Author(s): C.L. Yang, S. Tsuda, K. Umeo, T. Onimaru, W. Paschinger, G. Giester, P. Rogl, T. Takabatake
  • Journal Title: J. Alloys Compd. Volume: 739 Pages: 518-521
  • DOI: 10.1016/j.jallcom.2017.12.323
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Doping effects on the hybridization gap and antiferromagnetic order in the Kondo semiconductor CeOs2Al10 studied by break-junction experiments (2017)
  • Author(s): J. Kawabata, T. Ekino, Y. Yamada, Y. Okada, A. Sugimoto, Y. Muro, T. Takabatake
  • Journal Title: Phys. Rev. B 95 Volume: 95 Issue: 3
  • DOI: 10.1103/physrevb.95.035144
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Interplay between hybridization gap and antiferromagnetic gap in the hole-doped Kondo semiconductor Ce(Os1-yRey)2Al10 (2017)
  • Author(s): J. Kawabata, T. Ekino, Y. Yamada, A. Sugimoto, Y. Muro, T. Takabatake
  • Journal Title: J. Phys.: Conf. Ser. Volume: 807
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Uniaxial pressure effects on the unusual antiferromagnetic transition in the Kondo semiconductor CeOs2Al10 (2017)
  • Author(s): K. Hayashi, K. Umeo, Y. Yamada J. Kawabata, Y. Muro, T. Takabatake
  • Journal Title: J. Phys.: Conf. Ser. Volume: 807
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Dilution effects on the antiferromagnetic Kondo semiconductor CeOs2Al10 (2017)
  • Author(s): Y. Okada, J. Kawabata, Y. Yamada, Y. Muro, T. Takabatake
  • Journal Title: J. Phys.: Conf. Ser. Volume: 807
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Evolution of a magnetic order in the quasi-kagome lattice system CeRh1-xPdxSn (x< 0.75) (2017)
  • Author(s): C. L. Yang, K. Umeo, T. Takabatake
  • Journal Title: J. Phys.: Conf. Ser. Volume: 807 Pages: 042001-042001
  • DOI: 10.1088/1742-6596/807/4/042001
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Inelastic neutron scattering investigations of an anisotropic hybridization gap in the Kondo insulators: CeT2Al10 (T=Fe, Ru and Os) (2016)
  • Author(s): D.T. Adroja, Y. Muro, T. Takabatake, M.D. Le, H.C. Walker, K.A. McEwen, A.T. Boothroyd
  • Journal Title: Solid State Phenomena Volume: 257 Pages: 11-25
  • DOI: 10.4028/www.scientific.net/ssp.257.111
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Doping effects on the electronic structure of an antiferromagnetic Kondo semiconductor CeOs2Al10: An optical study with Re and Ir substitution (2016)
  • Author(s): S. Kimura, H. Takao, J. Kawabata, Y. Yamada, T. Takabatake
  • Journal Title: J. Phys. Soc. Jpn. Volume: 85 Issue: 12 Pages: 123705-123705
  • DOI: 10.7566/jpsj.85.123705
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Giant isotropic Nernst effect in an anisotropic Kondo semimetal (2016)
  • Author(s): U. Stoker, P. Sun, N. Oeschler, F. Steglich, T. Takabatake, P. Coleman, S. Paschen
  • Journal Title: Phys. Rev. Lett. Volume: 117 Issue: 21
  • DOI: 10.1103/physrevlett.117.216401
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Presentation] Magnetic Ordering in Cerium-based Kondo Semiconductors (2018)
  • Author(s): T. Takabatake
  • Organizer: The 21st Intern. Conf. on Solids Compounds of Transition Elements
  • Int'l Joint Research / Invited
• [Presentation] Quantum criticality in the quasi-kagome Kondo lattice CeRh1-xPdxSn (2017)
  • Author(s): C. L. Yang, 津田研, 梅尾和則, 鬼丸孝博, 山根悠, 高畠敏郎, 菊川直樹, 寺嶋太一, 宇治進也, D. T. Adroja
  • Organizer: 日本物理学会第７２回大会
  • Place of Presentation: 大阪大学豊中キャンパス（豊中市）
  • Year and Date: 2017-03-19
• [Presentation] パルスマグネットを用いた近藤半導体CeT2Al10 (T=Ru, Os, Fe)の圧力下磁気抵抗 (2017)
  • Author(s): 近藤晃弘, 金道浩一, 山本昇由, 片岡真一, 谷田博司, 世良正文, 川端丈, 高畠敏郎, 西岡孝
  • Organizer: 日本物理学会第７２回大会
  • Place of Presentation: 大阪大学豊中キャンパス（豊中市）
  • Year and Date: 2017-03-19
• [Presentation] 近藤半導体CeOs2Al10の三段のギャップに対する4f正孔及び5d正孔/電子ドープの効果 (2017)
  • Author(s): 川端丈, 浴野稔一, 岡田泰洋, 山田義大, 杉本暁, 室裕司, 高畠敏郎
  • Organizer: 日本物理学会第７２回大会
  • Place of Presentation: 大阪大学豊中キャンパス（豊中市）
  • Year and Date: 2017-03-18
• [Presentation] 近藤半導体CeT2Al10(T=Ru, Os)の一軸圧下における反強磁性転移の格子ひずみ依存性 (2017)
  • Author(s): 林慶介, 竹内崇志, 川端丈, 梅尾和則, 室裕司, 高畠敏郎
  • Organizer: 日本物理学会第７２回大会
  • Place of Presentation: 大阪大学豊中キャンパス（豊中市）
  • Year and Date: 2017-03-18
• [Presentation] Antiferromagnetic Ordering in Kondo Semiconductors CeT2Al10 (T = Ru, Os) (2017)
  • Author(s): T. Takabatake
  • Organizer: Korean Physical Society Spring Meeting 2017
  • Int'l Joint Research / Invited
• [Presentation] Roles of hybridization in the unusual antiferromagnetic order in Kondo semiconductors CeT2Al10 (T = Ru and Os) (2017)
  • Author(s): T. Takabatake
  • Organizer: International Conference on Strongly Correlated Electron Systems 2017
  • Int'l Joint Research
• [Presentation] Antiferromagnetic Kondo semiconductor CeOs2Al10 (2016)
  • Author(s): T. Takabatake
  • Organizer: 14th Bilateral Japanese-German Symposium on Effects of Parity Mixing in Correlated Electron Systems
  • Place of Presentation: Sapporo, Japan
  • Year and Date: 2016-09-29
  • Int'l Joint Research / Invited
• [Presentation] Evolution of a magnetic order in the quasi-kagome lattice system CeRh1-xPdxSn (2016)
  • Author(s): C. L. Yang, K. Umeo, T. Takabatake
  • Organizer: Intern. Conf. on Strongly Correlated Electron Systems
  • Place of Presentation: Hangzhou, China
  • Year and Date: 2016-09-15
  • Int'l Joint Research
• [Presentation] 反強磁性近藤半導体CeT2Al10(T = Ru, Os)のc-f混成および擬ギャップに対する一軸圧力効果 (2016)
  • Author(s): 林慶介, 竹内崇志, 川端丈, 梅尾和則, 室裕司, 高畠敏郎
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学（石川県 金沢市）
  • Year and Date: 2016-09-15
• [Presentation] 反強磁性近藤半導体CeOs2Al10の三段ギャップ構造に対するLa希釈効果 (2016)
  • Author(s): 川端丈, 浴野稔一, 岡田泰洋, 山田義大, 杉本暁, 室裕司, 高畠敏郎
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学（石川県 金沢市）
  • Year and Date: 2016-09-15
• [Presentation] CeOs2Al10の光学伝導度スペクトルのホール・電子ドープ効果 (2016)
  • Author(s): 木村真一, 高尾一, 山田義大, 川端丈, 高畠敏郎
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学（石川県 金沢市）
  • Year and Date: 2016-09-15
• [Presentation] 近藤半導体CeT2Al10(T = Ru, Os, Fe)の特異な反強磁性秩序に対する一軸圧力効果 (2016)
  • Author(s): 竹内崇志, 林慶介, 川端丈, 梅尾和則, 高畠敏郎, 室裕司
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学（石川県 金沢市）
  • Year and Date: 2016-09-15
• [Presentation] Magnetic criticality in a quasi-kagome Kondo lattice system CeRh1-xPdxSn (2016)
  • Author(s): C. Yang, 梅尾和則，山根悠, 鬼丸孝博, 高畠敏郎, D.T. Adroja
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学（石川県 金沢市）
  • Year and Date: 2016-09-15
• [Presentation] Dilution and doping effects on the antiferromagnetic Kondo semiconductor CeOs2Al10 (2016)
  • Author(s): T. Takabatake, Y. Okada, J. Kawabata, Y. Yamada, K. Hayashi, T. Ekino, Y. Muro
  • Organizer: Intern. Conf. on Strongly Correlated Electron Systems
  • Place of Presentation: Hangzhou, China
  • Year and Date: 2016-05-13
  • Int'l Joint Research
• [Presentation] Development of in-gap states in the antiferromagnetic Kondo semiconductor CeOs2Al10 by doping of 5d electrons and holes (2016)
  • Author(s): J. Kawabata, T. Ekino, Y. Yamada, A. Sugimoto, Y. Muro, T. Takabatake
  • Organizer: Intern. Conf. on Strongly Correlated Electron Systems
  • Place of Presentation: Hangzhou, China
  • Year and Date: 2016-05-10
  • Int'l Joint Research
• [Presentation] Uniaxial-pressure effect on the magnetic frustration in the Yb based triangular lattice antiferromagnet YbCuGe (2016)
  • Author(s): K. Hayashi, K. Umeo, Y. Yamada, J. Kawabata, Y. Muro, T. Takabatake
  • Organizer: Intern. Conf. on Strongly Correlated Electron Systems
  • Place of Presentation: Hangzhou, China
  • Year and Date: 2016-05-10
  • Int'l Joint Research