Interaction of a Neel-type skyrmion and a superconducting vortex

TL;DR

This paper investigates the interaction between Neel-type skyrmions and superconducting vortices in heterostructures, revealing conditions for vortex positioning, skyrmion size changes, and spontaneous vortex-antivortex pair generation due to stray fields.

Contribution

It introduces a theoretical model describing the energetics of skyrmion-vortex interactions, including the novel prediction of spontaneous vortex-antivortex pair formation.

Findings

Vortices can energetically prefer positions away from skyrmion centers.

Skyrmion radius increases with vortex-antivortex pair presence.

Spontaneous vortex-antivortex pair generation can occur under certain conditions.

Abstract

Superconductor-ferromagnet heterostructures hosting vortices and skyrmions are new area of an interplay between superconductivity and magnetism. We study an interaction of a Neel-type skyrmion and a Pearl vortex in thin heterostructures due to stray fields. Surprisingly, we find that it can be energetically favorable for the Pearl vortex to be situated at some nonzero distance from the center of the Neel-type skyrmion. The presence of a vortex-antivortex pair is found to result in increase of the skyrmion radius. Our theory predicts that a spontaneous generation of a vortex-anti-vortex pair is possible under some conditions in the presence of a Neel-type skyrmion.