Publicly Offered Research
Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
We formulated a general microscopic approach to spin-orbit torques in ferromagnet/heavy-metal bilayers in linear response to electric current or electric field [Physical Review B 95, 094401 (2017)]. The torques are directly related to a local spin polarization of conduction electrons, which is computed from generalized Kubo-Streda formulas.We have developed a multiscale magnetization dynamics simulation approach that can be applied to large systems with spin spiral structures that vary locally on small length scales [Physical Review B 94, 184415 (2016)]. We have shown that in a system with a Dzyaloshinskii-Moriya interaction leading to spin spirals, the simulated multiscale result is in good agreement with the analytical calculation.We developed a theory of Skyrmion Hall effect, which has been successfully observed by time-resolved x-ray microscopy [Nature Physics, 13, 170 (2017)]. We find that skyrmions move at a well-defined Skyrmion Hall angle, but in contrast to conventional theoretical expectations, it increases linearly with velocity. We explained our observation based on internal mode excitations in combination with a field-like spin-orbit torque, showing that one must go beyond the usual rigid skyrmion description to understand the dynamics.
28年度が最終年度であるため、記入しない。
All 2017 2016 2015
All Journal Article (10 results) (of which Int'l Joint Research: 9 results, Peer Reviewed: 10 results, Open Access: 4 results, Acknowledgement Compliant: 10 results) Presentation (36 results) (of which Int'l Joint Research: 34 results, Invited: 34 results)
Nature Physics
Volume: 13 Issue: 2 Pages: 170-175
10.1038/nphys4000
Physical Review B
Volume: 95 Issue: 9
10.1103/physrevb.95.094401
Volume: 94 Issue: 18
10.1103/physrevb.94.184415
Volume: 93 Issue: 5
10.1103/physrevb.93.054418
Physical Review Letters
Volume: 116 Issue: 14
10.1103/physrevlett.116.147203
Applied Physics Letters
Volume: 108 Issue: 12
10.1063/1.4944664
Volume: 93 Issue: 6
10.1103/physrevb.93.064428
Volume: 108 Issue: 13
10.1063/1.4944996
Journal of Magnetism and Magnetic Materials
Volume: 383 Pages: 65-68
10.1016/j.jmmm.2014.12.088
IEEE Transactions on Magnetics
Volume: 51 Issue: 9 Pages: 0800414-0800414
10.1109/tmag.2015.2436362
