Bulk and surface topological indices for a skyrmion string: current-driven dynamics of skyrmion string in stepped samples.

ABSTRACT: The magnetic skyrmion is a topological magnetic vortex, and its topological nature is characterized by an index called skyrmion number which is a mapping of the magnetic moments defined on a two-dimensional space to a unit sphere. In three-dimensions, a skyrmion, i.e., a vortex penetrating though the magnet naturally forms a string, which terminates at the surfaces of the magnet or in the bulk. For such a string, the topological indices, which control its topological stability are less trivial. Here, we study theoretically, in terms of numerical simulation, the dynamics of current-driven motion of a skyrmion string in a film sample with the step edges on the surface. In particular, skyrmion-antiskyrmion pair is generated by driving a skyrmion string through the side step with an enough hei

SUBMITTER: Koshibae W 

PROVIDER: S-EPMC7680146 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature