Geometry-induced motion of magnetic domain walls in curved nanostripes

TL;DR

This paper demonstrates that the curvature of a nanostripe can induce high-velocity motion of magnetic domain walls without external stimuli, driven by geometry-induced Dzyaloshinskii--Moriya interaction, applicable to various geometries.

Contribution

It introduces a novel mechanism for domain wall motion driven solely by geometric curvature gradients, expanding control methods for magnetic textures.

Findings

Domain walls reach velocities up to 100 m/s due to curvature gradients.

Motion is driven by inhomogeneous Dzyaloshinskii--Moriya interaction.

The approach is applicable to various curved geometries.

Abstract

Dynamics of topological magnetic textures are typically induced externally by, e.g.~magnetic fields or spin/charge currents. Here, we demonstrate the effect of the internal-to-the-system geometry-induced motion of a domain wall in a curved nanostripe. Being driven by the gradient of the curvature of a biaxial stripe, transversal domain walls acquire remarkably high velocities of up to 100 m/s and do not exhibit any Walker-type speed limit. We pinpoint that the inhomogeneous distribution of the curvature-induced Dzyaloshinskii--Moriya interaction is a driving force for the motion of a domain wall. Although we showcase our approach on the specific Euler spiral geometry, the approach is general and can be applied to a wide class of geometries.