Diffusive and Fluid-like Motion of Homochiral Domain Walls in Easy-Plane Magnetic Strips

TL;DR

This study uses micromagnetic simulations to show that easy-plane magnetic domain walls in strips transition from diffusive to fluid-like motion with increasing density, enabling robust spin transport for device applications.

Contribution

It reveals the transition from diffusive to fluid-like domain wall motion in magnetic strips, highlighting a new perspective on easy-plane spin transport beyond hydrodynamic models.

Findings

Domain walls transition from diffusive to fluid-like motion with increased density.

Notched nanostrips show unimpeded domain wall propagation in the fluid-like regime.

Spin transport via easy-plane precession is robust against defects in realistic ferromagnets.

Abstract

Propagation of easy-plane magnetic precession can enable more efficient spin transport than conventional spin waves. Such easy-plane spin transport is typically understood in terms of a hydrodynamic model, partially analogous to superfluids. Here, using micromagnetic simulations, we examine easy-plane spin transport in magnetic strips as the motion of a train of domain walls rather than as hydrodynamic flow. We observe that the motion transitions from diffusive to fluid-like as the density of domain walls is increased. This transition is most evident in notched nanostrips, where the the domain walls are pinned by the notch defect in the diffusive regime but propagate essentially unimpeded in the fluid-like regime. Our findings suggest that spin transport via easy-plane precession, robust against defects, is achievable in strips based on realistic metallic ferromagnets and hence amenable to practical device applications.