Deformation of the moving magnetic skyrmion lattice in MnSi under electric current flow

D Okuyama; M Bleuel; J S White; Q Ye; J Krzywon; G Nagy; Z Q Im; I Živković; M Bartkowiak; H M Rønnow; S Hoshino; J Iwasaki; N Nagaosa; A Kikkawa; Y Taguchi; Y Tokura; D Higashi; J D Reim; Y Nambu; T J Sato

doi:10.1038/s42005-019-0175-z

Deformation of the moving magnetic skyrmion lattice in MnSi under electric current flow

Commun Phys. 2019;2(1):10.1038/s42005-019-0175-z. doi: 10.1038/s42005-019-0175-z.

Authors

D Okuyama¹, M Bleuel^{2

3}, J S White^{4

5}, Q Ye³, J Krzywon², G Nagy⁵, Z Q Im⁴, I Živković⁴, M Bartkowiak⁶, H M Rønnow⁴, S Hoshino⁷, J Iwasaki⁸, N Nagaosa^{7

8}, A Kikkawa⁷, Y Taguchi⁷, Y Tokura^{7

8}, D Higashi¹, J D Reim¹, Y Nambu^{1

9}, T J Sato¹

Affiliations

¹ Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, Katahira 2-1-1, Sendai 980-8577, Japan.
² NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899-8562, USA.
³ Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742-2115, USA.
⁴ Laboratory for Quantum Magnetism, Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
⁵ Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland.
⁶ Laboratory for Scientific Developments and Novel Materials (LDM), Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland.
⁷ RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan.
⁸ Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan.
⁹ Institute for Materials Research (IMR), Tohoku University, Katahira 2-1-1, Sendai 980-8577, Japan.

Abstract

Topological defects are found ubiquitously in various kinds of matter, such as vortices in type-II superconductors, and magnetic skyrmions in chiral ferromagnets. While knowledge on the static behavior of magnetic skyrmions is accumulating steadily, their dynamics under forced flow is still a widely open issue. Here, we report the deformation of the moving magnetic skyrmion lattice in MnSi under electric current flow observed using small-angle neutron scattering. 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 j _t ~ 1 MA m^-2 (10⁶ A m^-2). Our result show that skyrmion lattices under current flow experience significant friction near the sample edges due to pinning, this being a critical effect that must be considered for anticipated skyrmion-based applications at the nanoscale.

Grants and funding

9999-NIST/ImNIST/Intramural NIST DOC/United States