Inertia in skyrmions confined to one-dimensional geometries

TL;DR

This paper demonstrates that magnetic skyrmions confined to one-dimensional geometries acquire mass due to the skyrmion Hall effect and elasticity, affecting their depinning and dynamic behavior, with implications for experimental observations.

Contribution

It reveals that skyrmions in 1D geometries have finite inertia, contrasting with the zero-mass assumption, and analyzes its effects on depinning and velocity behavior.

Findings

Skyrmion mass reduces the critical depinning force.

Mass causes step-like features in velocity-current curves.

Finite mass may induce hysteresis in skyrmion dynamics.

Abstract

Magnetic skyrmions are conventionally attributed to having zero mass. In contrast, we show that skyrmions confined to one-dimensional geometries generically acquire mass (inertia) due to the combined effects of the skyrmion Hall effect and the elasticity of the system. We investigate the massive behavior of the skyrmion for a simplified periodic model of the disorder. We show that skyrmion mass lowers the critical depinning force and leads to a step-like behavior in the skyrmion velocity-vs-current curves, which were recently observed in experiments. Finite mass could also lead to hysteresis in the velocity-vs-current curves.