Toggle-switch-like crossover between two types of isolated skyrmions within the conical phase of cubic helimagnets

TL;DR

This paper explores the field-induced transition between two types of isolated skyrmions in cubic helimagnets, revealing a crossover point and the transformation into meron pairs, with implications for complex skyrmion cluster states.

Contribution

It introduces the concept of a crossover between skyrmion types within the conical phase and analyzes their stability and transformations under magnetic fields.

Findings

Crossover occurs at the same field where skyrmion lattice stabilizes.

Perpendicular skyrmions are less stable than parallel ones.

Perpendicular skyrmions can transform into meron pairs.

Abstract

We investigate the field-induced crossover between two types of isolated skyrmions that exist within the conical phase of cubic helimagnets and orient themselves either along or perpendicular to the field. Such a crossover takes place for the same value of the field, at which the closely packed skyrmion lattice was predicted to stabilize in the A-phase region. The clusters and a skyrmion lattice comprised by the skyrmions perpendicular to the field, however, are unfavorable and lose their stability as compared with the skyrmions parallel to the field. We also followed transformation of perpendicular skyrmions into pairs of merons that rupture the helical state. An attractive interactions between different types of isolated skyrmions make it feasible to construct complex cluster states with the cubic arrangement of skyrmions.