Theoretical study of thermo-electric and thermo-magnetic response in transition-metal oxides

2008 Fiscal Year Final Research Report

• Project/Area Number: 18560043
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Applied physics, general
• Research Institution: The Institute of Physical and Chemical Research (2008); Sendai National College of Technology (2006-2007)
• Principal Investigator: KOSHIBAE Wataru The Institute of Physical and Chemical Research (20273253)
• Project Period (FY): 2006 – 2008
• Keywords: 熱電効果 / スピンと軌道の自由度

Research Abstract

我々は,遷移金属酸化物に代表される強相関電子系に対し電子のスピンと軌道の自由度を伴った伝導現象を理論的に調べ,熱電材料開発の新たな指導原理の構築を行ってきた.本計画では,とりわけ,熱磁気効果におけるスピンと軌道自由度の役割について理論的研究を行った.結果,軌道の自由度が作り出す,結晶構造とは異なる格子構造と,これを反映した新奇な熱磁気効果の可能性が指摘された.また,スピン自由度が織り成す新しい熱電現象に対する研究が行われた.

Research Products

• [Journal Article] Phenomenological analysis for spin-Seebeck effect in metallic magnets (2009)
  • Author(s): K. Uchida, S. Takahashi, J. Ieda, K. Harii, K. Ikeda, W. Koshibae, S. Maekawa, E. Saitoh
  • Journal Title: J. Appl. Phys. 105 Pages: 07C908-1-07C908-3
  • Peer Reviewed
• [Journal Article] Theo-retical study of thermoelectric and Hall ef-fects in the layered cobalt oxides, NaxCoO_2 (2008)
  • Author(s): W. Koshibae, A. Oguri, S. Maekawa
  • Journal Title: J. Phys. and Chem. Solids 69 Pages: 3214-3216
  • Peer Reviewed
• [Journal Article] Observation of the spin Seebeck effect (2008)
  • Author(s): K. Uchida, S. Takahashi, K. Harii, J. Ieda, W. Koshibae, K. Ando, S. Maekawa, E. Saitoh
  • Journal Title: Nature 455 Pages: 778-781
  • Peer Reviewed
• [Journal Article] Theoretical study of the electronic structure in β-pyrochlore oxides (2007)
  • Author(s): W. Koshibae, H. Murata, S. Maekawa
  • Journal Title: Journal of Magnet-ism and Magnetic Materials 310 Pages: 1005-1007
  • Peer Reviewed
• [Journal Article] Mag-netic correlations of the Hubbard model on frustrated lattices (2007)
  • Author(s): N. Bulut, W. Koshibae, S. Maekawa
  • Journal Title: Journal of Magnetism and Magnetic Materials 310 Pages: 511-513
  • Peer Reviewed
• [Journal Article] Hall effect in CoO2 layers with a hexagonal structure (2007)
  • Author(s): W. Koshibae, A. Oguri, S. Maekawa
  • Journal Title: Phys. Rev. B 75 Pages: 205115(1)- 205115(4)
  • Peer Reviewed
• [Presentation] Time evolution of excited state in the system with first-order metal-insulator transition (2009)
  • Author(s): W. Koshibae
  • Organizer: 2009 APS March Meeting
  • Place of Presentation: Pittsburgh, Penn-sylvania, USA
  • Year and Date: 2009-03-19
• [Presentation] Relaxation dynamics of ex-cited states in the double-exchange model (2009)
  • Author(s): W. Koshibae
  • Organizer: AIST-RIKEN Joint WS on "Emergent Phe-nomena of Correlated Materials"
  • Place of Presentation: Okinawa, Japan
  • Year and Date: 2009-03-05
• [Presentation] 金属から絶縁体への一次相転移を含む系における励起状態の時間発展 (2008)
  • Author(s): 小椎八重航
  • Organizer: 日本物理学会 2008年秋季大会
  • Place of Presentation: 岩手大学上田キャンパス
  • Year and Date: 20080920-23
• [Presentation] 強相関電子系の熱電効果におけるスピンと軌道の役割 (2008)
  • Author(s): 小椎八重航
  • Organizer: 次世代スーパーコンピュータプロジェクトナノ統合拠点の物性科学ワーキンググループ連続研究会 -新しい概念に基づく熱電材料とその物理-
  • Place of Presentation: 東北大学金属材料研究所
  • Year and Date: 2008-12-12
• [Presentation] Time evolution of excited state in the system with first-order metalin-sulator transition (2008)
  • Author(s): W. Koshibae
  • Organizer: The 2nd International Symposium on Anomalous Quantum Materials (ISAQM2008) and the 7th Asia-Pacific Workshop
  • Place of Presentation: Yasuda Auditorium, Univ. of Tokyo, Tokyo, Japan
  • Year and Date: 2008-11-08
• [Presentation] Theory of thermoelectric and thermomagnetic response in strongly correlated electron systems (2008)
  • Author(s): W. Koshibae
  • Organizer: E-MRS 2008 Spring Meeting
  • Place of Presentation: Congress Center, Strasbourg, France
  • Year and Date: 2008-05-29
• [Presentation] Thermo-magnetic effect of cobalt oxides (2008)
  • Author(s): W. Koshibae
  • Organizer: 2008 APS March Meeting
  • Place of Presentation: New Orleans, Louisiana, USA
  • Year and Date: 2008-03-14
• [Presentation] Theoretical Study of Ther-moelectric Response in Strongly Correlated Electron Systems (2007)
  • Author(s): W. Koshibae
  • Organizer: MRS 2007 Fall Meeting
  • Place of Presentation: Boston, MA, USA
  • Year and Date: 2007-11-28
• [Presentation] コバルト酸化物の熱磁気効果 (2007)
  • Author(s): 小椎八重航
  • Organizer: 日本物理学会第62回年次大会
  • Place of Presentation: 北海道大学
  • Year and Date: 2007-09-21
• [Presentation] Theory of thermopower in strongly correlated electron systems (2007)
  • Author(s): W. Koshibae
  • Organizer: 2007 APS March Meeting
  • Place of Presentation: Denver, Colorado, USA
  • Year and Date: 2007-03-05
• [Presentation] Theory of thermoelectric re-sponse in strongly correlated electron systems (2006)
  • Author(s): W. Koshibae
  • Organizer: First CoMePhS Workshop on PHASE SEPARATION IN ELECTRONIC SYSTEMS
  • Place of Presentation: Crete, Greece
  • Year and Date: 2006-10-31
• [Presentation] 強相関電子系の熱起電力におけるスピンと軌道の役割-異種の遷移金属を含む化合物の場合- (2006)
  • Author(s): 小椎八重航
  • Organizer: 日本物理学会2006年秋季大会
  • Place of Presentation: 千葉大学
  • Year and Date: 2006-09-23
• [Presentation] Theoretical study of the elec-tronic structure in β-pyrochlore oxides (2006)
  • Author(s): W. Koshibae
  • Organizer: In-ternational conference on magnetism
  • Place of Presentation: Kyoto International Conference Hall (KICH), Japan
  • Year and Date: 2006-08-23
• [Book] セラミックスの電磁的・光学的性質 (2006)
  • Author(s): 小椎八重 航
  • Total Pages: 119-123
  • Publisher: 社団法人日本セラミックス協会