Late stages in the ordering of magnetic skyrmion lattices

TL;DR

This study uses Langevin molecular dynamics simulations to analyze the late-stage ordering process of magnetic skyrmions, revealing how the Magnus force influences relaxation dynamics and transient properties.

Contribution

It introduces a novel analysis of skyrmion ordering by event histograms, distinguishing regimes dominated by Magnus force from noise effects during relaxation.

Findings

Magnus force accelerates skyrmion relaxation in certain regimes.

Event histograms exhibit power-law tails with exponents depending on Magnus force strength.

Transient properties of skyrmion matter are characterized during late-stage ordering.

Abstract

The late-stage ordering of interacting magnetic skyrmions is studied numerically through extensive Langevin molecular dynamics simulations. Defining skyrmion displacements that change the connectivity of cells obtained in a Voronoi tesselation as events, we investigate event histograms as a function of the time elapsed since preparing the system as well as the histograms of consecutive events as a function of the time separating these two events. These histograms, which provide unique insights into the transient properties during the ordering process of skyrmion matter, show a characteristic behavior that allows the Magnus-force dominated regime, where the Magnus force accelerates the relaxation process, to be distinguished from the noise-dominated regime, where the Magnus force enhances the effects of thermal noise. In the Magnus-force dominated regime the different histograms display power-law tails with exponents that depend on the strength of the Magnus force.