Electron nematic states in iron-based superconductors near the orbital-selective Mott transition

• Project/Area Number: 18K13492
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 13030:Magnetism, superconductivity and strongly correlated systems-related
• Research Institution: The University of Tokyo
• Principal Investigator: Mizukami Yuta 東京大学, 大学院新領域創成科学研究科, 助教 (80734095)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2019: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000); Fiscal Year 2018: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
• Keywords: 軌道選択モット転移 / 量子相転移 / XYネマティック / 電子ネマティック状態 / 長時間緩和法 / 精密比熱測定 / ネマティック感受率 / 弾性抵抗 / 鉄系超伝導体 / 電荷密度波 / 鉄系超伝導 / ネマティック状態

Outline of Final Research Achievements

We clarify that the nematic susceptibility along Fe-As direction is enhanced in heavily-hole doped iron-pnictide superconductors RbFe2As2 and CsFe2As2. In the intermediate regime of Ba-substituted system (Ba, Rb)Fe2As2, the nematic susceptibilities along Fe-As direction and Fe-Fe direction are simultaneously enhanced, suggesting the existence of XY nematicity in this regime. Furthermore, we perform field-angle resolved heat capacity measurement on RbFe2As2 using long relaxation method. This study provides thermodynamic evidence that the electronic state has two-fold symmetry which breaks the four-fold symmetry of the underlying crystal lattices.

Academic Significance and Societal Importance of the Research Achievements

本研究は過剰ホールドープ鉄系超伝導体において従来の電子ネマティック状態とは方向の異なる新規なネマティック状態が存在することを揺らぎや熱力学的な観点から明らかにしました。この性質は他の系との類似性も指摘されており、強相関電子の電子状態の普遍的な性質を理解する上で重要であると考えられます。また、置換系における結果はこれまで報告されていたネマティック状態よりも古典的なネマティックに似た状態が実現していることを示唆します。この新しく発見されたネマティック状態は、従来のものとは異なりその向きを自由に制御できるため、新しい素励起等の発見につながることが期待されます。

Research Products

• [Int'l Joint Research] Karlsruhe Institute of Technology(ドイツ)
• [Int'l Joint Research] University of Minnesota/University of Colorado/University of Minnesota(米国)
• [Int'l Joint Research] Ecole Polytechnique(フランス)
• [Int'l Joint Research] The Chinese University of Hong Kong(中国)
• [Int'l Joint Research] KAIST(韓国)
• [Int'l Joint Research] Ecole Polytechnique(フランス)
• [Journal Article] Effect of quenched disorder on the quantum spin liquid state of the triangular-lattice antiferromagnet 1T?TaS2 (2020)
  • Author(s): Murayama H.、Sato Y.、Taniguchi T.、Kurihara R.、Xing X. Z.、Huang W.、Kasahara S.、Kasahara Y.、Kimchi I.、Yoshida M.、Iwasa Y.、Mizukami Y.、Shibauchi T.、Konczykowski M.、Matsuda Y.
  • Journal Title: Physical Review Research Volume: 2 Issue: 1 Pages: 013099-013099
  • DOI: 10.1103/physrevresearch.2.013099
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Novel Electronic Nematicity in Heavily Hole-Doped Iron Pnictide Superconductors (2020)
  • Author(s): K. Ishida, M. Tsujii, S. Hosoi, Y. Mizukami, S. Ishida, A. Iyo, H. Eisaki, T. Wolf, K. Grube, H. v. Loehneysen, R. M. Fernandes, and T. Shibauchi,
  • Journal Title: Proc. Natl. Acad. Sci. USA Volume: 117 Issue: 12 Pages: 6424-6429
  • DOI: 10.1073/pnas.1909172117
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] 77Se-NMR Study under Pressure on 12%-S Doped FeSe (2019)
  • Author(s): Kuwayama Takanori、Matsuura Kohei、Mizukami Yuta、Kasahara Shigeru、Matsuda Yuji、Shibauchi Takasada、Uwatoko Yoshiya、Fujiwara Naoki
  • Journal Title: Journal of the Physical Society of Japan Volume: 88 Issue: 3 Pages: 033703-033703
  • DOI: 10.7566/jpsj.88.033703
  • NAID: 210000135114
  • Peer Reviewed
• [Journal Article] Unconventional thermal metallic state of charge-neutral fermions in an insulator (2019)
  • Author(s): Y. Sato, Z. Xiang, Y. Kasahara, T. Taniguchi, S. Kasahara, L. Chen, T. Asaba, C. Tinsman, H. Murayama, O. Tanaka, Y. Mizukami, T. Shibauchi, F. Iga, J. Singleton, Lu Li, and Y. Matsuda
  • Journal Title: Nature Physics Volume: 15 Issue: 9 Pages: 954-959
  • DOI: 10.1038/s41567-019-0552-2
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Diagonal nematicity in the pseudogap phase of HgBa2CuO4+δ (2019)
  • Author(s): Murayama H.、Sato Y.、Kurihara R.、Kasahara S.、Mizukami Y.、Kasahara Y.、Uchiyama H.、Yamamoto A.、Moon E.-G.、Cai J.、Freyermuth J.、Greven M.、Shibauchi T.、Matsuda Y.
  • Journal Title: Nature Communications Volume: 10 Issue: 1 Pages: 3282-3282
  • DOI: 10.1038/s41467-019-11200-1
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Universal relationship between low-energy antiferromagnetic fluctuations and superconductivity in BaFe2(As1?xPx)2 (2019)
  • Author(s): Kitagawa Shunsaku、Kawamura Takeshi、Ishida Kenji、Mizukami Yuta、Kasahara Shigeru、Shibauchi Takasada、Terashima Takahito、Matsuda Yuji
  • Journal Title: Physical Review B Volume: 100 Issue: 6 Pages: 060503-060503
  • DOI: 10.1103/physrevb.100.060503
  • Peer Reviewed
• [Journal Article] Measuring magnetic field texture in correlated electron systems under extreme conditions (2019)
  • Author(s): Yip King Yau、Ho Kin On、Yu King Yiu、Chen Yang、Zhang Wei、Kasahara S.、Mizukami Y.、Shibauchi T.、Matsuda Y.、Goh Swee K.、Yang Sen
  • Journal Title: Science Volume: 366 Issue: 6471 Pages: 1355-1359
  • DOI: 10.1126/science.aaw4278
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Majorana quantization and half-integer thermal quantum Hall effect in a Kitaev spin liquid (2018)
  • Author(s): Kasahara Y.、Ohnishi T.、Mizukami Y.、Tanaka O.、Ma Sixiao、Sugii K.、Kurita N.、Tanaka H.、Nasu J.、Motome Y.、Shibauchi T.、Matsuda Y.
  • Journal Title: Nature Volume: 559 Issue: 7713 Pages: 227-231
  • DOI: 10.1038/s41586-018-0274-0
  • NAID: 120006497340
  • Peer Reviewed
• [Journal Article] Evidence for s-wave pairing with atomic scale disorder in the van der Waals superconductor NaSn2As2 (2018)
  • Author(s): Ishihara K.、Takenaka T.、Miao Y.、Tanaka O.、Mizukami Y.、Usui H.、Kuroki K.、Konczykowski M.、Goto Y.、Mizuguchi Y.、Shibauchi T.
  • Journal Title: Physical Review B Volume: 98 Issue: 2 Pages: 1-5
  • DOI: 10.1103/physrevb.98.020503
  • Peer Reviewed / Int'l Joint Research
• [Presentation] 鉄系超伝導体FeSe1-xTexの電子相図の研究 (2020)
  • Author(s): 向笠清隆, 松浦康平, 杉村優一, 大谷椋, Mingwei Qiu, 斎藤三樹彦, 石田浩祐, 大西由吾, 水上雄太, 橋本顕一郎, 熊井玲児, 郷地順, 上床美也, 芝内孝禎
  • Organizer: 日本物理学会 第75回年次大会
• [Presentation] FeSe1-xTex(x=0.30)の常圧での核磁気共鳴 (2020)
  • Author(s): 中村昂矢, 桑山昂典, 松浦康平, 水上雄太, 笠原成, 松田祐司, 芝内孝禎, 上床美也, 藤原直樹
  • Organizer: 日本物理学会 第75回年次大会
• [Presentation] Fe(Se,Te)における電子ネマティック秩序 (2020)
  • Author(s): 石田浩祐, 大西由吾, 辻井優哉, 向笠清隆, 杉村優一, Mingwei Qiu, 松浦康平, 斎藤三樹彦, 水上雄太, 橋本顕一郎, 芝内孝禎
  • Organizer: 日本物理学会 第75回年次大会
• [Presentation] キタエフスピン液体候補物質α-RuCl3における磁場中比熱の異方性 (2020)
  • Author(s): 原澤龍平, 田中桜平, 水上雄太, 栗田伸之, 田中秀数, Eun-Gook Moon, 笠原裕一, 松田祐司, 橋本顕一郎, 芝内孝禎
  • Organizer: 日本物理学会 第75回年次大会
• [Presentation] A novel nematic state in heavily hole-doped iron-pnictides (2019)
  • Author(s): Y. Mizukami
  • Organizer: Superstripes 2019
  • Int'l Joint Research / Invited
• [Presentation] 弾性抵抗測定によるネマティック超伝導物質SrxBi2Se3の異方的ゆらぎの評価 (2019)
  • Author(s): 小江悠達, 細井優, 井澤公一, 石田浩祐, 辻井優哉, 水上雄太, 竹田駿, 笹川崇男, M. Hecker, J. Schmalian, 芝内孝禎
  • Organizer: 日本物理学会 2019年秋季大会
• [Presentation] 鉄系超伝導体FeSe1-xTexの温度・圧力・化学置換の三次元電子相図 (2019)
  • Author(s): 向笠清隆, 松浦康平, 杉村優一, 大谷椋, Mingwei Qiu, 水上雄太, 郷地順, 上床美也, 芝内孝禎
  • Organizer: 日本物理学会 2019年秋季大会
• [Presentation] FeSe1-xSx (x = 0.12)の反強磁性相における高圧下77Se-NMR測定 (2019)
  • Author(s): 桑山昂典, 松浦康平, 水上雄太, 笠原成, 松田祐司, 芝内孝禎, 上床美也, 藤原直樹
  • Organizer: 日本物理学会 2019年秋季大会
• [Presentation] FeSe1-xSx(x=0.05,0.12,0.23)の常圧での核磁気共鳴 (2019)
  • Author(s): 中村昂矢, 桑山昂典, 松浦康平, 水上雄太, 笠原成, 松田祐司, 芝内孝禎, 上床美也, 藤原直樹
  • Organizer: 日本物理学会 2019年秋季大会
• [Presentation] Ce系重い電子超伝導体における未解決問題 (2019)
  • Author(s): 水上雄太
  • Organizer: 領域8シンポジウム 「非従来型超伝導体の未解決問題と将来の展望」, 日本物理学会第74回年次大会
  • Invited
• [Presentation] Thermodynamic studies on iron-chalcogenides Fe(Se,S) in the BCS-BEC crossover (2018)
  • Author(s): Y. Mizukami
  • Organizer: 12th International Conference on Materials and Mechanisms of Superconductivity and High-Temperature Superconductivity (M2S-2018)
  • Int'l Joint Research / Invited
• [Presentation] Nematicity in heavily hole-doped iron-pnictides Ba1-xRbxFe2As2 (2018)
  • Author(s): Y. Mizukami
  • Organizer: 31th International Symposium on Superconductivity (ISS 2018)
  • Int'l Joint Research / Invited
• [Remarks] 東京大学大学院 新領域創成科学研究科 物質系専攻 凝縮系量子相物理学 研究室
  • URL: http://qpm.k.u-tokyo.ac.jp/index.html
• [Remarks] 個人HP
  • URL: https://sites.google.com/view/yutamizukamipage/home?authuser=0
• [Remarks]
  • URL: https://sites.google.com/view/yutamizukamipage/home
• [Remarks]
  • URL: https://scholar.google.co.jp/citations?hl=ja&user=WdynWbIAAAAJ