Theoretical and numerical studies on motion of magnetic domain wall in random field

• Project/Area Number: 19740243
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Single-year Grants
• Research Field: Mathematical physics/Fundamental condensed matter physics
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: MATSUSHITA Katsuyoshi National Institute of Advanced Industrial Science and Technology, ナノテクノロジー研究部門, 産総研特別研究員 (60422440)
• Project Period (FY): 2007 – 2008
• Project Status: Completed (Fiscal Year 2008)
• Budget Amount: ¥3,630,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥330,000); Fiscal Year 2008: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2007: ¥2,200,000 (Direct Cost: ¥2,200,000)
• Keywords: 磁壁運動 / スピントルク / 磁壁抵抗 / LLG方程式 / 磁壁 / シミュレーション / 双極子相互作用 / 磁気相図 / 有限サイズ効果 / ピン止め

Research Abstract

金属磁性体、希薄磁性半導体中における電流駆動磁壁運動の実験で観測されている性質を説明するため乱雑磁場によりピン止めされた磁壁の運動の理論的研究行った。数値計算による研究で磁壁の内部自由度が磁壁のダイナミクスに重要な役割を果たしていることが明らかにされ、そのため既存のランダム磁場中のIsing 模型や細線の磁壁にたいするスロンチェフスキの議論では知られていない不連続転移的な磁壁のデピンイング転移や磁壁そのものの電流誘起の変形現象などが明らかとなった。

Research Products

• [Journal Article] Dipolar field effect on microwave oscillation in a domain wall spin-valve (2009)
  • Author(s): Katsuyoshi Matsushita, Jun Sato, Hiroshi Imamura
  • Journal Title: IEEE Trans.Magn. (採録決定)
• [Journal Article] Current-Induced Magnetic Structure in Geometrically Confined Region (2009)
  • Author(s): Katsuyoshi Matsushita, Jun Sato, and Hiroshi Imamura
  • Journal Title: J. Magn. Phys. Soc. Jpn. vol.33 Pages: 274-279
  • NAID: 10025969912
• [Journal Article] Simulation of current-induced microwave oscillation in geometrically confined domain wall (2009)
  • Author(s): Katsuyoshi Matsushita, Jun Sato, and Hiroshi Imamura
  • Journal Title: J. Appl. Phys. 105, 07D525
• [Journal Article] Current-perpendicular-to-plane magnetoresistance of a domain wall confined in a nano-oxide-layer (2009)
  • Author(s): Jun Sato, Katsuyoshi Matsushita, and Hiroshi Imamura
  • Journal Title: J. Appl. Phys. 105, 07D101
• [Journal Article] Current-perpendicular-to-plane magnetoresistance of a domain wall confined in a nano-oxide-layer (2009)
  • Author(s): Jun Sato
  • Journal Title: Journal Applied Physics 105
  • Peer Reviewed
• [Journal Article] Simulation of current-induced microwave oscillation in geometrically confined domain wall (2009)
  • Author(s): Katsuyoshi Matsushita
  • Journal Title: Journal Applied Physics 105
  • Peer Reviewed
• [Journal Article] Magnetic structure of domain walls in confined in a nano-oxide layer (2008)
  • Author(s): Katsuyoshi Matsushita, Jun Sato, Hiroshi Imamura
  • Journal Title: IEEE Transaction in Magnetics 44, 2616
• [Journal Article] Effective Resistance Mismatch and Magnetoresistance of a CPP-GMR system with Current-Confine-Path (2008)
  • Author(s): Jun Sato, Katsuyoshi Matsushita, and Hiroshi Imamura
  • Journal Title: IEEE Transaction in Magnetics 44,2608
• [Journal Article] Effective Resistance Mismatch and Magnetoresistance of a CPP-GMR system with Current-Confined-Paths (2008)
  • Author(s): Jun Sato
  • Journal Title: IEEE Transaction on Magnetics 44 Pages: 2608-2692
  • Peer Reviewed
• [Journal Article] Magnetic structure of domain walls confined in a nano-oxide layer (2008)
  • Author(s): Katsuyoshi Matsushita
  • Journal Title: IEEE Transaction on Magnetics 44 Pages: 2616-2619
  • Peer Reviewed
• [Journal Article] Current-Induced Magnetic Structure in Geometrically Confined Region
  • Author(s): Katsuyoshi Matsushita
  • Journal Title: Journal of The Magnetics Society of Japan (In press)
  • NAID: 10025969912
  • Peer Reviewed
• [Presentation] Current induced geometrically confined magnetic structure and dynamics (2009)
  • Author(s): Katsuyoshi Matsushita
  • Organizer: SciSSP2009
  • Place of Presentation: 東京大学 物性研究所,柏
  • Year and Date: 2009-02-16
• [Presentation] Magnetic structures and dynamics of domain wall in Geometrically confined region (2009)
  • Author(s): Katsuyoshi Matsushita
  • Organizer: ISNTT2009
  • Place of Presentation: NTT R&Dセンター,厚木
  • Year and Date: 2009-01-20
• [Presentation] Effect of dipolar interaction on the current-induced microwave oscillation of a geometrically confined domain wall (2009)
  • Author(s): K. Matsushita, J. Sato and H. Imamura
  • Organizer: Intermag
  • Place of Presentation: Sacramento
• [Presentation] Current induced geometrically confined magnetic structure and dynamics (2009)
  • Author(s): K. Matsushita, J. Sato and H. Imamura
  • Organizer: SciSSP2009
  • Place of Presentation: 物性研究所, 柏
• [Presentation] Magnetic structures and dynamics of domain wall in Geometrically confined region (2009)
  • Author(s): K. Matsushita, J. Sato and H. Imamura
  • Organizer: ISNTT2009
  • Place of Presentation: NTTR&D センター, 厚木
• [Presentation] 幾何学的閉じ込め磁壁の電流駆動ダイナミクス (2009)
  • Author(s): 松下勝義、佐藤純、今村裕志
  • Organizer: 日本物理学会
  • Place of Presentation: 立教大学池袋キャンパス
• [Presentation] 電流狭窄領域をもつ磁性多層薄膜における磁気構造の理論的研究 (2008)
  • Author(s): 松下 勝義、佐藤 純、今村 裕志
  • Organizer: 日本物理学会
  • Place of Presentation: 大阪、近畿大学
  • Year and Date: 2008-03-24
• [Presentation] Current induced microwave oscillation of a geometrically confined domain wall (2008)
  • Author(s): K. Matsushita, J. Sato and H.Imamura
  • Organizer: MMM 2008
  • Place of Presentation: Austin
• [Presentation] Magnetic structure of domain wallsconfined in a nano-oxide layer Intermag 2008 (2008)
  • Author(s): K. Matsushita, J. Sato and H. Imamura
  • Organizer: Intermag 2008
  • Place of Presentation: Madrid
• [Presentation] 直流電流を印加した幾何学的閉じ込め磁壁 (2008)
  • Author(s): 松下勝義、佐藤純、今村裕志
  • Organizer: スピンが拓く物性科学の最前線
  • Place of Presentation: 東京大学武田先端知ビル
• [Presentation] 幾何学的閉じ込め磁壁での電流誘起磁化運動 (2008)
  • Author(s): 松下勝義、佐藤純、今村裕志
  • Organizer: 金属スピントロニクスセミナー
  • Place of Presentation: 東北大学工学部
• [Presentation] 電流狭窄領域に閉じ込められた磁壁の電流駆動ダイナミクス (2008)
  • Author(s): 松下勝義、佐藤純、今村裕志
  • Organizer: 日本物理学会
  • Place of Presentation: 岩手大学
• [Presentation] 狭窄型磁壁スピンバルブにおけるノイズ発生機構 (2008)
  • Author(s): 松下勝義、佐藤純、今村裕志
  • Organizer: 日本磁気学会
  • Place of Presentation: 東北学院大学 多賀城キャンパス
• [Presentation] 電流狭窄領域をもつ磁性多層薄膜における磁気構造の理論的研究 (2008)
  • Author(s): 松下勝義、佐藤純、今村裕志
  • Organizer: 日本物理学会 第62 回年次大会
  • Place of Presentation: 近畿大学
• [Presentation] 単純立方格子系の表面における双極子系の安定状態 (2007)
  • Author(s): 松下 勝義, 高山 一
  • Organizer: 日本物理学会
  • Place of Presentation: 札幌、北海道大学
  • Year and Date: 2007-09-22