Study to elucidate a driving mechanism of moving magnetic skyrmions in a nonequilibrium steady state and under an external field

• Project/Area Number: 17K14327
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: Tohoku University
• Principal Investigator: Daisuke Okuyama 東北大学, 多元物質科学研究所, 助教 (30525390)
• Project Period (FY): 2017-04-01 – 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 2018: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2017: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000)
• Keywords: 非平衡定常状態の物理 / 中性子散乱 / 磁気スキルミオン / 非平衡状態の物理 / 磁性

Outline of Final Research Achievements

To elucidate a nonequilibrium steady state of a magnetic skyrmion lattice under an external force, we study a small angle neutron diffraction experiment of typical chiral magent MnSi under an electric current flow. In our study, the deformation of the moving magnetic skyrmion lattice in MnSi under electric current flow observed. A spatially inhomogeneous rotation of the skyrmion lattice, with an inverse rotation sense for opposite sample edges, is observed for current densities greater than a threshold value jt ~ 1 MA/m2. Our result show that skyrmion lattices under current flow experience significant friction near the sample edges due to pinning and locally deforms like plastic matter when driven under electric current. This plastic deformation of the magnetic skyrmion lattice is a critical effect that must be considered for anticipated skyrmion-based applications at the nanoscale.

Academic Significance and Societal Importance of the Research Achievements

今回得られた研究結果より、外力によって駆動している磁気スキルミオン格子は試料端でのピニング効果により摩擦のような力を受け塑性変形を起こすことが分かった。駆動中の塑性変形はこれまで行われてきた磁気スキルミオン研究では考慮されず、薄膜や細線等のデバイスとして磁気スキルミオンを利用する際にバルク試料と異なった性質を示す一因になっているのではと予想する。本研究成果は磁気スキルミオンを使った記憶媒体などを実現するのに必要不可欠な新しい知見を示したため、本研究の波及効果は大きいと考えている。

Research Products

• [Int'l Joint Research] NIST/ORNL(米国)
• [Int'l Joint Research] PSI/EPFL(スイス)
• [Int'l Joint Research] ANSTO(オーストラリア)
• [Int'l Joint Research] NIST/ORNL(米国)
• [Int'l Joint Research] PSI(スイス)
• [Int'l Joint Research] ANSTO(Australia)
• [Int'l Joint Research] NIST(米国)
• [Int'l Joint Research] PSI(Switzerland)
• [Journal Article] Effect of Ge substitution on magnetic properties in the itinerant chiral magnet MnSi (2019)
  • Author(s): Aji Seno, Ishida Hidesato, Okuyama Daisuke, Nawa Kazuhiro, Hong Tao, Sato Taku J.
  • Journal Title: Physical Review Materials Volume: 3 Issue: 10 Pages: 104408-104408
  • DOI: 10.1103/physrevmaterials.3.104408
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Deformation of the moving magnetic skyrmion lattice in MnSi under electric current flow (2019)
  • Author(s): D. Okuyama, M. Bleuel, J.S. White, Q. Ye, J. Krzywon, G. Nagy, Z.Q. Im, I. Zivkovic, M. Bartkowiak, H.M. Ronnow, S. Hoshino, J. Iwasaki, N. Nagaosa, A. Kikkawa, Y. Taguchi, Y. Tokura, D. Higashi, J.D. Reim, Y. Nambu, T.J. Sato
  • Journal Title: Communications Physics Volume: 2 Issue: 1 Pages: 79-79
  • DOI: 10.1038/s42005-019-0175-z
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] 電流下における磁気スキルミオン格子の塑性変形 (2019)
  • Author(s): 奥山大輔, 東大樹, 南部雄亮, 佐藤卓
  • Journal Title: 波紋 Volume: 29 Pages: 171-175
  • NAID: 130007949162
  • Peer Reviewed
• [Journal Article] Controlling the stoichiometry of the triangular lattice antiferromagnet Li1+xZn2-yMo3O8 (2019)
  • Author(s): Sandvik Kim E.、Okuyama Daisuke、Nawa Kazuhiro、Avdeev Maxim、Sato Taku J.
  • Journal Title: Journal of Solid State Chemistry Volume: 271 Pages: 216-221
  • DOI: 10.1016/j.jssc.2018.12.064
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Crystal Structure in Quadrupolar Kondo Candidate PrTr2Al20 (Tr = Ti and V) (2019)
  • Author(s): Okuyama Daisuke、Tsujimoto Masaki、Sagayama Hajime、Shimura Yasuyuki、Sakai Akito、Magata Atsushi、Nakatsuji Satoru、Sato Taku J
  • Journal Title: Journal of the Physical Society of Japan Volume: 88 Issue: 1 Pages: 015001-015001
  • DOI: 10.7566/jpsj.88.015001
  • Peer Reviewed / Open Access
• [Journal Article] Degenerate ground state in the classical pyrochlore antiferromagnet Na3Mn(CO3)2Cl (2018)
  • Author(s): Nawa Kazuhiro、Okuyama Daisuke、Avdeev Maxim、Nojiri Hiroyuki、Yoshida Masahiro、Ueta Daichi、Yoshizawa Hideki、Sato Taku J.
  • Journal Title: Physical Review B Volume: 98 Issue: 14
  • DOI: 10.1103/physrevb.98.144426
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Spin Seebeck effect in the polar antiferromagnet α-Cu2V2O7 (2017)
  • Author(s): Y. Shiomi, R. Takashima, D. Okuyama, G. Gitgeatpong, P. Piyawongwatthana, K. Matan, T. J. Sato, E. Saitoh
  • Journal Title: Physical Review B Volume: 96 Issue: 18 Pages: 180414-180414
  • DOI: 10.1103/physrevb.96.180414
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Thermal stability and irreversibility of skyrmion-lattice phases in Cu2OSeO3 (2017)
  • Author(s): K. Makino, J. D. Reim, D. Higashi, D. Okuyama, T. J. Sato, Y. Nambu, E. P. Gilbert, N. Booth, S. Seki, Y. Tokura
  • Journal Title: Physical Review B Volume: 95 Issue: 13
  • DOI: 10.1103/physrevb.95.134412
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Impact of minute-time-scale kinetics on the stabilization of the skyrmion-lattice in Cu2OSeO3 (2017)
  • Author(s): J. D. Reim, K. Makino, D. Higashi, Y. Nambu, D. Okuyama, T. J Sato, E. P. Gilbert, N. Booth, S. Seki
  • Journal Title: J. Phys.: Conf. Ser. Volume: 828 Pages: 012004-012004
  • DOI: 10.1088/1742-6596/828/1/012004
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Creating the hydrogen absorption capability of CeNi5 through the addition of Al (2017)
  • Author(s): R. Yamagishi, T. Kojima, S. Kameoka, D. Okuyama, T. J. Sato, C.i Nishimura, A. P. Tsai
  • Journal Title: International J. Hydrogen Energy Volume: 42 Issue: 34 Pages: 21832-21840
  • DOI: 10.1016/j.ijhydene.2017.07.072
  • Peer Reviewed
• [Presentation] マルチフェロイック正方晶ペロブスカイトSr1/2Ba1/2MnO3の強誘電原子変位の観測 (2020)
  • Author(s): 奥山大輔,山内邦彦,酒井英明,田口康二郎,十倉好紀,杉本邦久,佐藤卓,小口多美夫
  • Organizer: 日本物理学会第75回年次大会（2020年）, 名古屋
• [Presentation] 電流下における磁気スキルミオン格子の動力学 (2019)
  • Author(s): 奥山大輔
  • Organizer: 展開共同研究 B 及び小口中村研合同研究会
  • Invited
• [Presentation] カイラル磁性体Pr5Ru3Al2の中性子小角散乱 (2019)
  • Author(s): 奥山大輔
  • Organizer: 東北大金研-CROSSワークショップ「J-PARCとJRR-3の相補利用による偏極中性子科学の新展開」
• [Presentation] 電流中の磁気スキルミオン格子のダイナミクス (2019)
  • Author(s): 奥山大輔
  • Organizer: 東北大金研-CROSSワークショップ「J-PARCとJRR-3の相補利用による偏極中性子科学の新展開」
  • Invited
• [Presentation] 量子ビームによる反転対称性が破れた磁性体の磁気的・電気的特性発現機構の解明 (2019)
  • Author(s): 奥山大輔
  • Organizer: 物質・デバイス領域共同研究拠点第9回活動報告会/平成30年度ダイナミック・アライアンス成果
  • Invited
• [Presentation] カイラル磁性体の電流効果に関する研究 (2019)
  • Author(s): 奥山大輔,山内邦彦,小口多美夫,佐藤卓
  • Organizer: 物質・デバイス領域共同研究拠点第9回活動報告会/平成30年度ダイナミック・アライアンス成果報告会
• [Presentation] 中性子散乱によるトポロジカル磁性の研究 (2019)
  • Author(s): 奥山大輔,那波和宏,佐藤卓
  • Organizer: 物質・デバイス領域共同研究拠点第9回活動報告会/平成30年度ダイナミック・アライアンス成果報告会
• [Presentation] Spatial Inhomogeneous Deformation of the Moving Magnetic Skyrmion Lattice in MnSi under Electric Current Flow (2019)
  • Author(s): D. Okuyama,M. Bleuel,J.S. White,Q. Ye,J. Krzywon,G. Nagy,Z.Q. Im,I. Zivkovic,M. Bartkowiak,H.M. Ronnow,S. Hoshino,J. Iwasaki,N. Nagaosa,A. Kikkawa,Y. Taguchi,Y. Tokura,D. Higashi,J.D. Reim,Y. Nambu,T.J. Sato
  • Organizer: International Conference on Strongly Correlated Electron Systems (SCES) 2019
  • Int'l Joint Research
• [Presentation] Magnetic properties in the itinerant chiral magnet MnSi1-xGex (2019)
  • Author(s): S. Aji,H. Ishida,D. Okuyama,K. Nawa,T. Hong,S. Yano,T. J Sato
  • Organizer: International Conference on Strongly Correlated Electron Systems 2019
  • Int'l Joint Research
• [Presentation] 中性子回折による磁気スキルミオン格子の電流駆動観測 (2019)
  • Author(s): 奥山大輔,山内邦彦,小口多美夫,佐藤卓
  • Organizer: 第7回アライアンス若手研究交流会プログラム
• [Presentation] Plastic deformation of the moving magnetic skyrmion lattice in MnSi under electric current flow (2019)
  • Author(s): D. Okuyama,M. Bleuel,J.S. White,Q. Ye,J. Krzywon,G. Nagy,Z.Q. Im,I. Zivkovic,M. Bartkowiak,H. M. Ronnow,S. Hoshino,J. Iwasaki,N. Nagaosa,A. Kikkawa,Y. Taguchi,Y. Tokura,D. Higashi,J. D. Reim,Y. Nambu,T. J. Sato
  • Organizer: The 3rd Asia-Oceania Conference on Neutron Scattering 2019 (AOCNS 2019)
  • Int'l Joint Research
• [Presentation] 中性子回折による電流下の磁気スキルミオン格子の非平衡定常/非定常状態 (2019)
  • Author(s): 奥山大輔,東大樹,南部雄亮,佐藤卓
  • Organizer: 第19回東北大学多元物質科学研究所研究発表会
• [Presentation] Absolute structure of α-Cu2V2O7 (2019)
  • Author(s): Pharit Piyawongwatthana,Daisuke Okuyama,Kazuhiro Nawa,Kittiwit Matan,Taku J Sato
  • Organizer: 日本物理学会2019秋季大会
• [Presentation] 立方晶カイラル磁性体Pr5Ru3Al2の磁気相図及び中性子小角散乱 (2019)
  • Author(s): 奥山大輔,牧野晃也,J. D. Reim,E. P. Gilbert,N. Booth,大石一城,山内邦彦,小口多美夫,佐藤卓
  • Organizer: 日本物理学会2019秋季大会
• [Presentation] 中性子非弾性散乱と放射光精密構造解析によるPrTr2Al20(Tr = Ti, V)の結晶構造特性と結晶場解析 (2019)
  • Author(s): 奥山大輔, 辻本真規, 佐賀山基, 志村恭通, 酒井明人, 眞方篤史, O. Garlea, B. Weing, 中辻知, 佐藤卓
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] Magnetic properties in the itinerant chiral magnet MnSi1-xGex (2019)
  • Author(s): Seno Aji, Hidesato Ishida, Daisuke Okuyama, Kazuhiro Nawa, Tao Hong, and Taku J Sato
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] PrTr2Al20 (Tr = Ti, V)の精密結晶構造と結晶場の解析 (2019)
  • Author(s): 奥山大輔, 辻本真規, 佐賀山基, 志村恭通, 酒井明人, 眞方篤史, 中辻知, 佐藤卓
  • Organizer: 2018年度量子ビームサイエンスフェスタ
• [Presentation] Kinetics of the magnetic skyrmion lattice in MnSi under direct/alternating electric current (2019)
  • Author(s): D. Okuyama, M. Bleuel, Q. Ye, N. Nagaosa, A. Kikkawa, Y. Taguchi, Y. Tokura, J. D. Reim, Y. Nambu and T. J. Sato
  • Organizer: The 2nd Symposium for World Leading Research Centers ‐ Materials Science and Spintronics ‐
  • Int'l Joint Research
• [Presentation] MnSi の定常/変動電流中の磁気スキルミオン格子ダイナミクス (2018)
  • Author(s): 奥山大輔, M. Bleuel, 永長直人, 吉川明子, 田口康二郎, 十倉好紀, 東大樹, J. D. Reim, 南部雄亮, 佐藤卓
  • Organizer: 日本中性子科学会 第18回年会
• [Presentation] MnSiにおける変動電流中の磁気スキルミオン格子のダイナミクス (2018)
  • Author(s): 奥山大輔, M. Bleuel, Q. Ye, P. Butler, 永長直人, 吉川明子, 田口康二郎, 十倉好紀, 東大樹, 南部雄亮, 佐藤卓
  • Organizer: 日本物理学会2018年度秋季大会
• [Presentation] MnSiにおける電流中の磁気スキルミオン格子の塑性流動的な振る舞い (2018)
  • Author(s): 奥山大輔, M. Bleuel, Q. Ye, P. Butler, 永長直人, 吉川明子, 田口康二郎, 十倉好紀, 東大樹, 南部雄亮, 佐藤卓
  • Organizer: 日本物理学会2018年度秋季大会
• [Presentation] 歪んだカゴメ格子反強磁性体Yb3Ni11Ge4の磁気散漫散乱 (2018)
  • Author(s): 高橋満, 那波和宏, Matthias Frontzek, 奥山大輔, 吉田雅洋, 植田大地, 吉沢英樹, 野尻浩之, 佐藤卓, Maxim Avdeev
  • Organizer: 日本物理学会2018年秋季大会
• [Presentation] Stabilizing the Skyrmion Phase in Cu2OSeO3: The Influence of Field, Temperature and Time (2018)
  • Author(s): Johannes D. Reim, Koya Makino, Daiki Higashi, Daisuke Okuyama, Taku J Sato, Yusuke Nambu, Elliot P. Gilbert, Norman Booth, Shinichiro Seki, Yoshinori Tokura
  • Organizer: International Conference on Magnetism 2018
  • Int'l Joint Research
• [Presentation] Degenerate ground state in classical pyrochlore antiferromagnet Na3Mn(CO3)2Cl (2018)
  • Author(s): Kazuhiro Nawa, Daisuke Okuyama, Maxim Avdeev, Hiroyuki Nojiri, Masahiro Yoshida, Daichi Ueta, Hideki Yoshizawa, and Taku J Sato
  • Organizer: International Conference on highly Frustrated Magnetism 2018
  • Int'l Joint Research
• [Presentation] パイロクロア格子反強磁性体Na3T(CO3)2Cl(T=Co, Mn)における磁化過程 (2018)
  • Author(s): 那波和宏, 野尻浩之, 奥山大輔, M. Avdeev, 吉田雅洋, 植田大地, 吉澤英樹, 佐藤卓
  • Organizer: 日本物理学会第70回年次大会
• [Presentation] パイロクロア格子反強磁性体Na3T(CO3)2Cl(T=Co, Mn)の磁性 (2017)
  • Author(s): 那波和宏, 奥山大輔, M. Avdeev, 野尻浩之, 吉田雅洋, 植田大地, 吉澤英樹, 佐藤卓
  • Organizer: 日本中性子科学会第17回年会
• [Presentation] MnSiで観測される磁気スキルミオン反射の回転とブロードニングの特異な電流密度及び温度依存性 (2017)
  • Author(s): 奥山大輔, M. Bleuel, Q. Ye, P. Butler, 星野晋太郎, 岩崎惇一, 永長直人, 吉川明子, 田口康二郎, 十倉好紀, 東大樹, 南部雄亮, 佐藤卓
  • Organizer: 日本物理学会2017年度秋季大会
• [Presentation] Controlling the stoichiometry of the triangular lattice antiferromagnet Li1+xZn2-yMo3O8 (2017)
  • Author(s): K. Sandvik, K. Nawa, D. Okuyama, J. Reim, M. Avdeev, M. Matsuda, T. J. Sato
  • Organizer: 日本物理学会2017年度秋季大会
• [Presentation] S=5/2パイロクロア格子反強磁性体Na3Mn(CO3)2Clの構造と磁性 (2017)
  • Author(s): 那波和宏, 奥山大輔, M. Avdeev, 野尻浩之, 佐藤卓
  • Organizer: 日本物理学会2017年度秋季大会
• [Presentation] 歪んだ籠目格子系Yb3Ni11Ge4の構造と低温物性 (2017)
  • Author(s): 高橋満, 那波和宏, 奥山大輔, 佐藤卓
  • Organizer: 日本物理学会2017年度秋季大会
• [Presentation] Influence of path and time on the stabilization of the skyrmion-lattice phases in Cu2OSeO3 (2017)
  • Author(s): J. D. Reim, K. Makino, D. Higashi, D. Okuyama, T. J. Sato, Y. Nambu, E. P. Gilbert , N. Booth, S. Seki, Y. Tokura
  • Organizer: 日本物理学会2017年度秋季大会
• [Presentation] Magnetic structure determined by small angle neutron and powder neutron scatterings in cubic chiral crystal Pr5Ru3Al2 (2017)
  • Author(s): K. Makino, D. Okuyama, M. Avdeev, K. Ohishi, K. Yamauchi, T. Oguchi, T. J. Sato
  • Organizer: International Conference on Neutron Scattering 2017 (ICNS 2017)
  • Int'l Joint Research
• [Presentation] Phase stability and higher order peaks of the skyrmion lattice in Cu2OSeO3 (2017)
  • Author(s): J. D. Reim, K. Makino, D. Higashi, Y. Nambu, D. Okuyama, T. J. Sato, E. P. Gilbert, N. Booth, S. Seki, Y. Tokura
  • Organizer: International Conference on Neutron Scattering 2017 (ICNS 2017)
  • Int'l Joint Research
• [Presentation] Helical magnetic structure in cubic chiral crystal Pr5Ru3Al2 (2017)
  • Author(s): K. Makino, D. Okuyama, M. Avdeev, K. Ohishi, K. Yamauchi, T. Oguchi, T. J. Sato
  • Organizer: 24th Congress and General Assembly of the International Union of Crystallography (IUCR2017)
  • Int'l Joint Research
• [Remarks] 流動中の磁気スキルミオン格子の変形挙動観測に成功
  • URL: http://www2.tagen.tohoku.ac.jp/lab/news_press/20190712/
• [Remarks] 若手研究者のタイトなつながりが、斬新な成果を生み出す
  • URL: http://five-star.tagen.tohoku.ac.jp/talk/talk_01.html