低次元フラストレート系におけるカイラル及び多極子秩序とその動的観測量

• Project Area: Novel States of Matter Induced by Frustration
• Project/Area Number: 22014016
• Research Category: Grant-in-Aid for Scientific Research on Priority Areas
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: The Institute of Physical and Chemical Research
• Principal Investigator: 桃井 勉 独立行政法人理化学研究所, 古崎物性理論研究室, 専任研究員 (80292499)
• Co-Investigator(Kenkyū-buntansha): 引原 俊哉 群馬大学, 大学院・工学研究科, 准教授 (00373358) ; 佐藤 正寛 青山学院大学, 理工学部, 助教 (90425570)
• Project Period (FY): 2010 – 2011
• Project Status: Completed (Fiscal Year 2011)
• Budget Amount: ¥1,800,000 (Direct Cost: ¥1,800,000); Fiscal Year 2011: ¥700,000 (Direct Cost: ¥700,000); Fiscal Year 2010: ¥1,100,000 (Direct Cost: ¥1,100,000)
• Keywords: スピンネマティック相 / 三角格子 / J1-J2ジグザグ鎖 / 動的物理量 / 多体スピン交換模型 / 磁気相図 / フラストレート磁性体 / スピン密度波 / スピンネマティック / スピンカイラリティー / 核磁気共鳴緩和率 / 磁気フラストレーション / 低次元量子スピン系 / 変分モンテカルロ法 / ボゾン化法 / 密度行列繰り込み群法

Research Abstract

スピンネマティック相の出現を理論的に検証すると同時に、その特性を明らかにするために、以下の研究を行った。1.固体ヘリウム3薄膜の核磁性を記述する三角格子多体スピン交換模型において、スピンネマティック状態が基底状態に現れることを示した。また、この模型は、最近の固体ヘリウム3薄膜の磁化曲線中に観測されたせまい1/2磁化プラトーを良く再現することを確認した。これらの結果から、固体ヘリウム3薄膜において、スピンネマティック状態が実現していることが期待される。(桃井)2.正方格子上のJ1-J2スピン模型において、最近接相互作用J1が強磁性の時、J1とJ2の競合が強い領域において、スピンネマティック相が出現することを変分モンテカルロ計算により示した。(桃井)3.N自由度を持つ一般化したJ1-J2スピン模型を用いてスピンネマティック状態を記述し、1/N展開法によりスピンネマティック相における動的物理量の振る舞いを明らかにした。(桃井)4.近年、擬1次元銅酸化物フラストレート磁性体(LiCuv04など)が、マルチフェロイクスおよび多極子秩序相を示す系として、注目を集めている。これらは全て最近接強磁性相互作用J1と次近接反強磁性相互作用J2を持つJ1-J2スピン鎖構造を有している。我々は、J1-J2スピン鎖模型に3次元鎖間結合を加えた系を調べ、温度磁場相図を完成させた。鎖間結合の種類に依存しながらスピン密度波相またはネマティック相が低温で現れることを定量的に示した。(佐藤、引原、桃井)5.開放端をもつ系のハミルトニアンにある種のエネルギー変調を施すことで、系の基底状態における開放端の効果を完全に無効化し、周期系と全く同じ基底状態を実現することが可能であることを明らかにした。この結果は低次元フラストレート系にも適用可能であり、今後の当該研究分野の進展に大きく寄与することが期待される。(引原)

Research Products

• [Journal Article] Spin nematic order in multiple-spin exchange models on the triangular lattice (2012)
  • Author(s): T.Momoi, P.Sindzingre, K.Kubo
  • Journal Title: Phys.Rev.Lett. Volume: 108(5) Issue: 5
  • DOI: 10.1103/physrevlett.108.057206
  • Peer Reviewed
• [Journal Article] Spin-chirality separation and S3-symmetry breakings in the magnetization plateau of the quantum spin tube (2012)
  • Author(s): Kouichi Okunishi, Masahiro Sato, Toru Sakai, Kiyomi Okamoto, and Chigak. Itoi
  • Journal Title: Phys. Rev. B Volume: 85 Issue: 5 Pages: 54416-54416
  • DOI: 10.1103/physrevb.85.054416
  • Peer Reviewed
• [Journal Article] NMR relaxation rate in the field-induced octupolar liquid phase of spin-1/2 J1-J2 frustrated chains (2011)
  • Author(s): M.Sato, T.Hikihara, T.Momoi
  • Journal Title: Journal of Physics : Conference Series Volume: 320 Pages: 012014-012014
  • DOI: 10.1088/1742-6596/320/1/012014
  • Peer Reviewed
• [Journal Article] Projective studies of spin nematics in a quantum frustrated ferromagnet (2011)
  • Author(s): R.Shindou, S.Yunoki, T.Momoi
  • Journal Title: Physical Review B Volume: 84(13) Issue: 13
  • DOI: 10.1103/physrevb.84.134414
  • Peer Reviewed
• [Journal Article] Phase diagram of the classical Heisenberg antiferromagnet on a triangular lattice in an applied magnetic field (2011)
  • Author(s): L.Seabra, T.Momoi, P.Sindzingre, N.Shannon
  • Journal Title: Physical Review B Volume: 84(21) Issue: 21
  • DOI: 10.1103/physrevb.84.214418
  • Peer Reviewed
• [Journal Article] Competing phases in spin-1/2 J_1-J_2 chain with easy-plane anisotropy (2011)
  • Author(s): M.Sato, S.Onoda
  • Journal Title: Mondern Phys.Letters B Volume: 25 Issue: 12n13 Pages: 901-908
  • DOI: 10.1142/s0217984911026607
  • Peer Reviewed
• [Journal Article] Sine-square deformation of free fermion systems in one and higher dimensions (2011)
  • Author(s): I.Maruyama, H.Katsura, T.Hikihara
  • Journal Title: Phys.Rev.B Volume: 84 Issue: 16
  • DOI: 10.1103/physrevb.84.165132
  • Peer Reviewed
• [Journal Article] Field and temperature dependence of the NMR relaxation rate in the magnetic quadrupolar liquid phase of spin-1/2 frustrated ferromagnetic chains (2011)
  • Author(s): M.Sato, T.Hikihara, T.Momoi
  • Journal Title: Phys.Rev.B Volume: 83
  • Peer Reviewed
• [Journal Article] Competing phases in spin-1/2 J_1-J_2 chain with easy-plane anisotropy (2011)
  • Author(s): M.Sato, S.Furukawa, S.Onoda, A.Furusaki
  • Journal Title: Modern Physics Letter B Volume: (印刷中)
  • Peer Reviewed
• [Journal Article] Connecting distant ends of one-dimensional critical systems by a sine-square deformation (2011)
  • Author(s): Toshiya Hikihara, Tomotoshi Nishino
  • Journal Title: Phys.Rev.B Volume: (印刷中)
  • Peer Reviewed
• [Journal Article] 磁性体中のスピンの量子ネマティック状態 (2010)
  • Author(s): 桃井勉
  • Journal Title: 日本物理学会誌 Volume: 65 Pages: 345-348
  • Peer Reviewed
• [Journal Article] Quantum spin nanotubes-frustration, competing orders and criticalities (2010)
  • Author(s): T.Sakai, M.Sato, K.Okunishi, K.Okamoto, C.Itoi
  • Journal Title: J.Phys.: Condens.Matter Volume: 22
  • Peer Reviewed
• [Journal Article] Coefficients of bosonized dimer operators in spin-1/2 XXZ chains and their applications (2010)
  • Author(s): S.Takayoshi, M.Sato
  • Journal Title: Phys.Rev.B Volume: 82
  • Peer Reviewed
• [Presentation] 磁場中三角格子古典ハイゼンベルグ模型の相転移 (2012)
  • Author(s): Luis Seabra、桃井勉、Philippe Sindzingre、Nic Shannon
  • Organizer: 日本物理学会第67回年次大会
  • Place of Presentation: 関西学院大学
  • Year and Date: 2012-03-25
• [Presentation] 低次元磁性体における多極子及びカイラリティ秩序相とそのダイナミクスについての理論研究 (2012)
  • Author(s): 佐藤正寛
  • Organizer: 日本物理学会第67回年次大会
  • Place of Presentation: 関西学院大(招待講演)
  • Year and Date: 2012-03-24
• [Presentation] Edge state and its stability of 2D antiferromagnetic quantum spin systems (2012)
  • Author(s): Takafumi Suzuki, Masahiro Sato
  • Organizer: APS March Meeting
  • Place of Presentation: Boston Convention Center, Boston, USA
  • Year and Date: 2012-02-29
• [Presentation] Competition between Spin Nematic and Spin Density Wave Orders in Spatially Anisotropic Frustrated Magnets in Magnetic Fields (2012)
  • Author(s): Masahiro Sato, Toshiya Hikihara, Tsutomu Momoi
  • Organizer: APS March Meeting
  • Place of Presentation: Boston Convention Center, Boston, USA
  • Year and Date: 2012-02-28
• [Presentation] 二次元量子系におけるサイン二乗変形の効果 (2012)
  • Author(s): 引原俊哉, 丸山勲, 桂法称
  • Organizer: 科研費特定領域研究「フラストレーションが創る新しい物性」最終成果報告会
  • Place of Presentation: 大阪大学
• [Presentation] Theory for Raman scattering in 1D spin-1/2 antiferromagnets : Effects of frustration and perturbations on the Heisenberg model (2011)
  • Author(s): Masahiro Sato
  • Organizer: Novel Quantum States in Condensed Matter 2011 (NQS2011)
  • Place of Presentation: Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto
  • Year and Date: 2011-11-14
• [Presentation] Edge states and their stability of 2D antiferromagnets (2011)
  • Author(s): Takafumi Suzuki, Masahiro Sato
  • Organizer: Novel Quantum States in Condensed Matter 2011 (NQS2011)
  • Place of Presentation: Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto
  • Year and Date: 2011-11-14
• [Presentation] New phases induced by four-spin interaction in stacked triangular-lattice antiferromagnets in magnetic field (2011)
  • Author(s): Shintaro Takayoshi, Masahiro Sato
  • Organizer: Novel Quantum States in Condensed Matter 2011 (NQS2011)
  • Place of Presentation: Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto
  • Year and Date: 2011-11-14
• [Presentation] 三角格子多体スピン交換模型におけるスピンネマティック状態の秩序変数 (2011)
  • Author(s): 桃井勉、Philippe Sindzingre、久保健
  • Organizer: 日本物理学会2011年秋季大会
  • Place of Presentation: 富山大学
  • Year and Date: 2011-09-22
• [Presentation] 一次元量子臨界系におけるsine-square deformationの効果 (2011)
  • Author(s): 引原俊哉, 西野友年
  • Organizer: 日本物理学会2011年秋季大会
  • Place of Presentation: 富山大学
  • Year and Date: 2011-09-21
• [Presentation] Theory of Raman Scattering Spectrum for One-Dimensional Quantum Magnets (2011)
  • Author(s): Masahiro Sato, Hosho Katsura, Naoto Nagaosa
  • Organizer: SCES2011
  • Place of Presentation: University of Cambridge, Cambridge, UK
  • Year and Date: 2011-08-02
• [Presentation] Effect of Four-Spin Interactions on Phase Diagram of Classical Heisenberg Antiferromagnets on Stacked Triangular Lattice Under Magnetic Field (2011)
  • Author(s): Shintaro Takayoshi, Masahiro Sato
  • Organizer: SCES2011
  • Place of Presentation: University of Cambridge, Cambridge, UK
  • Year and Date: 2011-08-02
• [Presentation] Variational Monte Carlo study of spin nematic states in square lattice frustrated ferromagnets (2011)
  • Author(s): T.Momoi, R.Shindou, S.Yunoki
  • Organizer: International Conference on Frustration in Condensed Matter (ICFCM)
  • Place of Presentation: Sendai
  • Year and Date: 2011-01-14
• [Presentation] ジグザグスピン梯子系におけるスピン多極子秩序の観測可能性 (2011)
  • Author(s): 引原俊哉, 佐藤正寛, 桃井勉, 古崎昭
  • Organizer: 科研費特定領域研究「フラストレーションが創る新しい物性」第7回トピカルミーティング「フラストレーションとスピン・電荷・軌道・格子自由度」
  • Place of Presentation: 彦根
• [Presentation] 磁場中フラストレート強磁性スピン鎖におけるカイラル相・スピン多極子相とその観測可能性 (2011)
  • Author(s): 引原俊哉
  • Organizer: 強相関電子系理論の最前線-若手によるオープン・イノベーション-
  • Place of Presentation: 紀伊勝浦(招待講演)
• [Presentation] Seven competing phases in the spin-1/2 frustrated J1-J2 chain with easy-plane anisotropy (2011)
  • Author(s): M.Sato, S.Furukawa, S.Onoda, A.Furusaki
  • Organizer: International Conference on Frustration in Condensed Matter (ICFCM)
  • Place of Presentation: Sendai
• [Presentation] Spin Dynamics in field-induced quadrupolar and octupolar liquid states in spin-1/2 frustrated chains (2011)
  • Author(s): M.Sato, T.Hikihara, T.Momoi
  • Organizer: International Conference on Frustration in Condensed Matter (ICFCM)
  • Place of Presentation: Sendai
• [Presentation] Entanglement entropy in 1D critical systems with open boundaries and Sinusoidal deformation (2010)
  • Author(s): 引原俊哉
  • Organizer: New Development of Numerical Simulations in Low-Dimensional Quantum Systems : From Density Matrix Renormalization Group to Tensor Network Formulations
  • Place of Presentation: 京都
  • Year and Date: 2010-10-27
• [Presentation] Spin dynamics in multipolar phases of one-dimensional quantum frustrated ferromagnet (2010)
  • Author(s): M.Sato, T.Hikihara, T.Momoi, A.Furusaki
  • Organizer: Quantum Matter in Low Dimensions : Opportunities and Challenges
  • Place of Presentation: Stockholm, Sweden
  • Year and Date: 2010-09-06
• [Presentation] Ferromagnetic transition in one-dimensional spin-1/2 Bose and Fermi gases (2010)
  • Author(s): M.Sato, S.Takayoshi, S.Furukawa
  • Organizer: Quantum Matter in Low Dimensions : Opportunities and Challenges
  • Place of Presentation: Stockholm, Sweden
  • Year and Date: 2010-09-06
• [Presentation] Spin nematic order and magnetization plateau in a multiple-spin exchange model on the triangular lattice (2010)
  • Author(s): T.Momoi, K.Kubo, P.Sindzingre
  • Organizer: 5th International Conference on Highly Frustrated Magnetism (HFM 2010)
  • Place of Presentation: Baltimore, USA
  • Year and Date: 2010-08-03
• [Presentation] Spin nematics in spin 1/2 frustrated magnets (2010)
  • Author(s): T.Momoi
  • Organizer: International Conference on Frustrated Spin Systems, Cold Atoms, Nanomaterials
  • Place of Presentation: Hanoi, Vietnam
  • Year and Date: 2010-07-16
• [Presentation] Successive transitions between Neel and dimer phases in spin-1/2 ferromagnetic frustrated chain with easy-plane anisotropy (2010)
  • Author(s): M.Sato, S.Furukawa, A.Furusaki
  • Organizer: The International Conference on Frustrated Spin Systems, Cold Atoms, Nanomaterials : Satellite Conference of StatPhys24
  • Place of Presentation: Hanoi Vietnam
  • Year and Date: 2010-07-15
• [Presentation] Determination of coefficients of bosonized dimer operators in spin-1/2 antiferromagnetic chains and their application (2010)
  • Author(s): S.Takayoshi, M.Sato
  • Organizer: The International Conference on Frustrated Spin Systems, Cold Atoms, Nanomaterials : Satellite Conference of StatPhys24
  • Place of Presentation: Hanoi, Vietnam
  • Year and Date: 2010-07-15
• [Presentation] Phase diagram and competing orders of stacked spatially anisotropic triangular Heisenberg antiferromagnets in magnetic field (2010)
  • Author(s): M.Sato, N.Todoroki
  • Organizer: The International Conference on Frustrated Spin Systems, Cold Atoms, Nanomaterials : Satellite Conference of StatPhys24
  • Place of Presentation: Hanoi, Vietnam
  • Year and Date: 2010-07-15
• [Presentation] Stability of collinear and coplanar phases in stacked spatially-anisotropic triangular antiferromagnets under a magnetic field (2010)
  • Author(s): M.Sato, N.Todoroki
  • Organizer: Highly Frustrated Magnetism 2010
  • Place of Presentation: Baltimore, USA
• [Presentation] NMR relaxation rate and dynamical structure factors in field-induced magnetic multi-polar phases of spin-1/2 frustrated ferromagnetic chains (2010)
  • Author(s): M.Sato, T.Hikihara, T.Momoi, A.Furusaki
  • Organizer: Highly Frustrated Magnetism 2010
  • Place of Presentation: Baltimore, USA
• [Presentation] Successive Neel and dimer orderings in spin-1/2 ferromagnetic frustrated chain with easy-plane anisotropy (2010)
  • Author(s): M.Sato, S.Furukawa, A.Furusaki
  • Organizer: Highly Frustrated Magnetism 2010
  • Place of Presentation: Baltimore, USA