Formation of In-plane Skyrmions in Epitaxial MnSi Thin Films as Revealed by Planar Hall Effect

TL;DR

This study reveals the formation of in-plane skyrmions in epitaxial MnSi thin films through planar Hall effect measurements, highlighting the role of uniaxial magnetic anisotropy in stabilizing these skyrmions.

Contribution

It demonstrates the detection and stabilization of in-plane skyrmions in MnSi thin films using planar Hall effect, a novel approach for thin film skyrmion research.

Findings

Stepwise planar Hall effect profile in bulk MnSi confirms skyrmion phase.

Detection of planar Hall anomalies indicates in-plane skyrmion strings.

Uniaxial magnetic anisotropy stabilizes in-plane skyrmions in thin films.

Abstract

We investigate skyrmion formation in both a single crystalline bulk and epitaxial thin films of MnSi by measurements of planar Hall effect. A prominent stepwise field profile of planar Hall effect is observed in the well-established skyrmion phase region in the bulk sample, which is assigned to anisotropic magnetoresistance effect with respect to the magnetic modulation direction. We also detect the characteristic planar Hall anomalies in the thin films under the in-plane magnetic field at low temperatures, which indicates the formation of skyrmion strings lying in the film plane. Uniaxial magnetic anisotropy plays an important role in stabilizing the in-plane skyrmions in the MnSi thin film.