Skyrmion Dynamics in Multiferroic Insulator

TL;DR

This paper explores how electric fields can manipulate Skyrmion motion in insulating multiferroic materials, revealing new control mechanisms without relying on conduction electrons, and identifies various resonance modes induced by AC electric fields.

Contribution

It demonstrates electric field-induced Skyrmion Hall motion and resonance modes in an insulating multiferroic, providing novel methods for Skyrmion manipulation without spin transfer torque.

Findings

Electric field causes Skyrmion Hall motion orthogonal to the field gradient.

Finite Gilbert damping results in longitudinal Skyrmion motion.

Resonance modes are excited by AC electric fields.

Abstract

Recent discovery of Skyrmion crystal phase in insulating multiferroic compound Cu$_2$OSeO$_3$ calls for new ways and ideas to manipulate the Skyrmions in the absence of spin transfer torque from the conduction electrons. It is shown here that the position-dependent electric field, pointed along the direction of the average induced dipole moment of the Skyrmion, can induce the Hall motion of Skyrmion with its velocity orthogonal to the field gradient. Finite Gilbert damping produces longitudinal motion. We find a rich variety of resonance modes excited by a.c. electric field.