Chiral magnetic skyrmions across length scales

TL;DR

This paper develops extended analytical formulae for the profile and energy of chiral skyrmions across a wide range of sizes, incorporating effects of external fields, anisotropy, and magnetostatics, enhancing understanding of their stability and structure.

Contribution

The authors extend existing asymptotic formulae for chiral skyrmions to cover nearly the entire size spectrum, including effects of external influences and magnetostatics.

Findings

Extended formulae accurately describe skyrmion profiles across sizes.

Magnetostatic fields significantly influence skyrmion structure.

Comparison with magnetic bubbles highlights differences in stabilization mechanisms.

Abstract

The profile and energy of chiral skyrmions, found in magnetic materials with the Dzyaloshinskii-Moriya interaction, can be approximated by formulae obtained through asymptotic analysis in the limits of small and large skyrmion radius. Using fitting techniques, we modify these formulae so that their validity extends to almost the entire range of skyrmion radii. Such formulae are obtained for skyrmions that are stabilised in the presence of an external field or easy-axis anisotropy or a combination of these. We further study the effect of the magnetostatic field on the skyrmion profile. We compare the profile of magnetic bubbles, stabilized without the chiral Dzyaloshinskii-Moriya interaction to that of a chiral skyrmion.