Dynamics of domain walls in curved antiferromagnetic wires

TL;DR

This paper investigates how curvature in antiferromagnetic wires affects domain wall dynamics, revealing curvature-induced pinning and driving forces, with analytical and numerical validation across various geometries.

Contribution

It introduces a theoretical framework for understanding curvature effects on antiferromagnetic domain walls, including pinning and motion without external stimuli.

Findings

Curvature creates a pinning potential for domain walls.

Gradient of curvature can drive domain wall motion.

Analytical predictions are confirmed by numerical simulations.

Abstract

The influence of the curvature on the dynamical properties of transversal domain walls in a thin antiferromagnetic wire is studied theoretically. Equations of motion for antiferromagnetic domain wall are obtained within the collective variable approach ($q-\Phi$ model). It is shown that (i) for the case of localized bend, curvature results in a pinning potential for domain wall. (ii) The gradient of the curvature results in a driving force on the domain wall and it effectively moves without any external stimuli. Although we showcase our approach on the specific parabola and Euler spiral geometries, the approach is general and valid for a wide class of geometries. All analytical predictions are confirmed by numerical simulations.