Topological magnons in skyrmion-lattice phases

• Project/Area Number: 17K18744
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics and related fields
• Research Institution: Tohoku University
• Principal Investigator: Sato Taku 東北大学, 多元物質科学研究所, 教授 (70354214)
• Project Period (FY): 2017-06-30 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥6,500,000 (Direct Cost: ¥5,000,000、Indirect Cost: ¥1,500,000); Fiscal Year 2018: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2017: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000)
• Keywords: magnetic skyrmion / neutron scattering / small angle scattering / inelastic scattering / topological magnon / 中性子非弾性散乱 / 磁気スカーミオン / マグノン / 物質探索 / 小角散乱 / 物性実験 / トポロジカルマグノン / トポロジー / スカーミオン

Outline of Final Research Achievements

Magnetic skyrmion lattice, a lattice of swirling topological magnetic texture, is predicted theoretically to host “topological bands” of quantized collective dynamics of magnetic moments, or “magnons”. In this study, we searched such topological magnons experimentally. First, we studied magnetic properties of various doped systems, such as Mn(Si,Ge), and found the appropriate systems to explore the topological magnons. In the neutron inelastic experiment, we observed a very broad inelastic excitation spectrum characteristic to the skyrmion lattice phase. This result is apparently not consistent with the theoretical predication, nonetheless, our numerical simulation suggests that the broadness is due to the finite temperature effect.

Academic Significance and Societal Importance of the Research Achievements

磁性体中に形成される磁気スカーミオンはその非自明なトポロジーに起因して外乱から保護された構造であると考えられるため、基礎科学の側面からだけでなく、スピントロニクス応用の観点からも興味が持たれている。本研究で我々は磁気スカーミオン中の準粒子マグノン（磁気モーメントの集団運動）に対してトポロジカルバンド形成の検証を行った。結果は予想されたものとは異なっていたが、磁気スカーミオン格子における有限温度のミクロな磁気ダイナミクスを明らかにしたという意味で基礎科学的に意義があると考える。

Research Products

• [Int'l Joint Research] Oak Ridge National Laboratory/NIST(米国)
• [Int'l Joint Research] ANSTO/University of Sydney(オーストラリア)
• [Int'l Joint Research] Paul Scherrer Institute(スイス)
• [Int'l Joint Research] Julich Center for Neutron Scattering/IFW(ドイツ)
• [Int'l Joint Research] University of Groningen(オランダ)
• [Int'l Joint Research] Oak Ridge National Laboratory/NIST(米国)
• [Int'l Joint Research] ANSTO/University of Sydney(オーストラリア)
• [Int'l Joint Research] Julich Center for Neutron Scattering/IFW(ドイツ)
• [Int'l Joint Research] Paul Scherrer Institute(スイス)
• [Int'l Joint Research] University of Groningen(オランダ)
• [Int'l Joint Research]
• [Int'l Joint Research] Oak Ridge National Laboratory/NIST/University of Maryland(米国)
• [Int'l Joint Research] Mahidol University/Phranakhon Rajabhat University(Thailand)
• [Int'l Joint Research] ANSTO(Australia)
• [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] Whirling spin order in the quasicrystal approximant Au72Al14Tb14 (2019)
  • Author(s): T. J. Sato, A. Ishikawa, A. Sakurai, M. Hattori, M. Avdeev, R. Tamura
  • Journal Title: PHYSICAL REVIEW B Volume: VOL. 100 Issue: 5
  • DOI: 10.1103/physrevb.100.054417
  • Peer Reviewed / Int'l Joint Research
• [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] 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] Nonreciprocal Magnons in Noncentrosymmetric Magnets (2019)
  • Author(s): Sato Taku J、Matan Kittiwit
  • Journal Title: Journal of the Physical Society of Japan Volume: 88 Issue: 8 Pages: 081007-081007
  • DOI: 10.7566/jpsj.88.081007
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Triplon band splitting and edge states in the quantum dimer compound Ba2CuSi2O6Cl2 (2018)
  • Author(s): K. Nawa, K. Tanaka, N. Kurita, T. J. Sato, H. Sugiyama, H. Uekusa, S. Ohira-Kawamura, K. Nakajima, S. Itoh, K. Kuwahara, and H. Tanaka
  • Journal Title: Nature Communications Volume: 印刷中 Issue: 1
  • DOI: 10.1038/s41467-019-10091-6
  • 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] Scaling of Memories and Crossover in Glassy (2017)
  • Author(s): A. M. Samarakoon, M. Takahashi, D. Zhang, J. Yang, N. Katayama, R. Sinclair, H. D. Zhou, S. O. Diallo, G. Ehlers, D. A. Tennant, S. Wakimoto, K. Yamada, G-W.Chern, T. J. Sato, S.-H. Lee
  • Journal Title: Magnets Scientific Reports Volume: 7 Issue: 1 Pages: 1-8
  • DOI: 10.1038/s41598-017-12187-9
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Topological magnetic textures and topological magnetic excitations (2020)
  • Author(s): 佐藤 卓
  • Organizer: The 20th Korea-Taiwan-Japan Symposium on Strongly Correlated Electron Systems
  • Int'l Joint Research / 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] Triplon band splitting and topologically protected edge states in the dimerized antiferromagnet (2019)
  • Author(s): Kazuhiro Nawa,Kimihiko Tanaka,Nobuyuki Kurita,Taku J Sato,Haruki Sugiyama,Hidehiro Uekusa,Seiko Ohira-Kawamura,Kenji Nakajima,Hidekazu Tanaka
  • Organizer: The 3rd Asia-Oceania Conference on Neutron Scattering 2019 (AOCNS 2019)
  • Int'l Joint Research
• [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] 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] Magnetic structures of quasicrystal approximants (2019)
  • Author(s): 佐藤 卓
  • Organizer: Interdisciplinary Symposium for Quasicrystals and Strongly Correlated Electron Systems
  • Int'l Joint Research / Invited
• [Presentation] Topological Magnetic Textures and Excitations (2019)
  • Author(s): 佐藤 卓
  • Organizer: INTERNATIONAL CONFERENCE ON ADVANCED MATERIAL TECHNOLOGY IN CONJUNCTION WITH INTERNATIONAL CONFERENCE OF MULTIDISCIPLINARY RESEARCH 2019 (ICAMT-ICMR 2019)
  • Int'l Joint Research / Invited
• [Presentation] Quantum condensed matter & WAND2 University users (2019)
  • Author(s): 佐藤 卓
  • Organizer: WAND2「Complementarity and Synergy effects with the JRR3 Instrument Suite」
  • Int'l Joint Research / Invited
• [Presentation] Quantum magnetism and topological magnetic structures (2019)
  • Author(s): 佐藤 卓
  • Organizer: International School of Crystallography 53rd Course: Magnetic Crystallography
  • Int'l Joint Research / Invited
• [Presentation] Topological triplon band and edge states in the spin dimer antiferromagnet Ba2CuSi2O6Cl2 (2018)
  • Author(s): Kazuhiro Nawa, Kimihiko Tanaka, Nobuyuki Kurita, Taku J Sato, Haruki Sugiyama, Hidehiro Uekusa, Seiko Ohira-Kawamura, Kenji Nakajima, and Hidekazu Tanaka
  • Organizer: The 2nd Asia Pacific Workshop on Quantum Magnetism
  • Int'l Joint Research / Invited
• [Presentation] 反転対称性の破れた磁性体中のマグノン非相反性 (2018)
  • Author(s): 佐藤 卓
  • Organizer: 磁性材料研究会
  • Invited
• [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] Ga-Pd-Tb系Tsai型近似結晶の形成と磁性III (2018)
  • Author(s): 高木強平, 肖英紀, 佐藤卓
  • Organizer: 日本物理学会 2018年秋季大会
• [Presentation] Au-Al-Tb 近似結晶の磁気構造 (2018)
  • Author(s): 佐藤卓, 石川明日香, 櫻井晶, Maxim Avdeev, 田村隆治
  • Organizer: 日本物理学会 2018年秋季大会
• [Presentation] S=1/2異方的三角格子反強磁性体Cs2CuCl4の非弾性中性子散乱による磁気励起測定 (2018)
  • Author(s): 村崎遼, 那波和宏, 中島健次, 河村聖子, Tao Hong, 佐藤卓
  • Organizer: 日本物理学会 2018年秋季大会
• [Presentation] MAGNETIC SKYRMIONS: THERMAL STABILITY,KINETICS AND ELECTRIC-CURRENT EFFECT (2018)
  • Author(s): Taku J. Sato
  • Organizer: XVII International Small Angle Scattering Conference - SAS2018
  • Int'l Joint Research / Invited
• [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, J. D Reim, 東大樹, 南部雄亮, 佐藤卓
  • Organizer: 日本物理学会 2018年秋季大会
• [Presentation] 中性子散乱による Al-Al-Yb の量子臨界磁気揺動観測 (2018)
  • Author(s): 佐藤卓, 米山祐樹, 廣川慎之介, 出口和彦, 佐藤憲昭, 益田隆嗣, 松浦直人, 柴田薫
  • 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): Reim, Johannes D., Makino, Koya., Higashi, Daiki., Okuyama, Daisuke., Sato, Taku J.,Nambu, Yusuke. Gilbert, Elliot P., Booth, Norman., Seki, Shinichiro., Tokura, Yoshinori
  • Organizer: International Conference on Magnetism 2018
  • Int'l Joint Research
• [Presentation] Neutron diraction study and theoretical analysis of the antiferromagnetic order and diuse scattering in the layered Kagome system CaBaCo2Fe2O7 (2018)
  • Author(s): J. D. Reim, E. Ros en, O. Zaharko, M. Mostovoy, M. Valldor, T. J. Sato, W. Schweika
  • Organizer: International Conference on Highly Frustrated 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] Nonreciprocal Magnons in Noncentrosymmetric Magnets (2018)
  • Author(s): Taku J Sato
  • Organizer: ISSP Workshop Present and Future of Neutron Scattering Research on Condensed Matter Physics - Future Perspective of US-Japan Cooperative Program on Neutron Scattering
  • Int'l Joint Research / Invited
• [Presentation] パイロクロア格子反強磁性体Na3T(CO3)2Cl（T = Co，Mn）の磁化過程 (2018)
  • Author(s): 那波和宏, 野尻浩之, 奥山大輔, Maxim Avdeev, 吉田雅洋, 植田大地, 吉澤英樹, 佐藤卓
  • Organizer: 日本物理学会 第73回年次大会
• [Presentation] Ga-Pd-Tb系Tsai型近似結晶の形成と磁性II (2018)
  • Author(s): 高木強平, 肖英紀, 佐藤卓
  • Organizer: 日本物理学会第73回年次大会
• [Presentation] Magnons in Noncentrosymmetric Magnets (2017)
  • Author(s): Taku Sato
  • Organizer: Gordon Research Conference
  • Int'l Joint Research / Invited
• [Presentation] THERMAL STABILITY AND SLOW DYNAMICS OF THE SKYRMION-LATTICE PHASES IN CU2OSEO3 (2017)
  • Author(s): Taku J Sato
  • Organizer: MATERIALS RESEARCH SOCIETY-INDONESIA CONFERENCE AND CONGRESS 2017
  • Int'l Joint Research / Invited
• [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
  • Int'l Joint Research
• [Presentation] Phase stability and higher order peaks of the skyrmion lattice in Cu2OSeO3 International Conference on Neutron Scattering 2017 (2017)
  • Author(s): Johannes D. Reim, Koya Makino, Daiki Higashi, Yusuke Nambu, Daisuke Okuyama, Taku J. Sato, Elliot P. Gilbert, Norman Booth, Shinichiro Seki, Yoshinori Tokura
  • Organizer: International Conference on Neutron Scattering 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
  • Int'l Joint Research
• [Presentation] Influence of path and time on the stabilization of the skyrmion-lattice phases in Cu2OSeO3 (2017)
  • 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: 日本物理学会2017年度秋季大会
• [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] フラストレーションの強いS=1スピンダイマー磁性体Ba2NiSi2O6Cl2における磁気励起 (2017)
  • Author(s): 栗田伸之, 那波和宏, 佐藤卓, 河村聖子, 中島健次, 田中秀数
  • Organizer: 日本物理学会2017年秋季大会
• [Presentation] 擬2次元量子スピンダイマー系Ba2CuSi2O6Cl2の磁気励起 (2017)
  • Author(s): 田中公彦, 栗田伸之, 那波和宏, 佐藤卓, 河村聖子, 中島健次, 桑原慶太郎, 伊藤晋一, 田中秀数
  • Organizer: 日本物理学会2017年秋季大会
• [Presentation] 非弾性中性子散乱を用いた梯子型鉄系化合物 BaFe2Se3 の磁性に対する研究 (2017)
  • Author(s): 羽合孝文, 南部雄亮, 大串研也, Barry Winn, V. Ovidiu Garlea, Melissa Graves-Brook, Igor Zaliznyak, 伊藤晋一, 横尾哲也, 佐藤卓
  • Organizer: 日本物理学会2017年秋季大会
• [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年秋季大会
• [Presentation] フラストレーションの強いS=1スピンダイマー磁性体Ba2NiSi2O6Cl2における局在励起 (2017)
  • Author(s): 栗田伸之, 那波和宏, 佐藤卓, 河村聖子, 中島健次, 田中秀数
  • Organizer: 日本中性子科学会第17回年会
• [Remarks] QSPL, IMRAM, Tohoku University
  • URL: http://www2.tagen.tohoku.ac.jp/lab/sato_tj/
• [Remarks] 東北大学多元物質科学研究所 スピン量子物性研究分野
  • URL: http://www2.tagen.tohoku.ac.jp/lab/sato_tj/