Antiskyrmions and their electrical footprint in crystalline mesoscale structures of Mn$_{1.4}$PtSn

TL;DR

This study demonstrates the electrical detection of antiskyrmions in crystalline Mn$_{1.4}$PtSn structures using combined magneto-optical microscopy and electrical transport, revealing their Hall signatures and dependence on various parameters.

Contribution

It provides the first experimental observation of antiskyrmions' electrical footprint in mesoscale structures, supported by theoretical and atomistic simulations.

Findings

Hall signature of antiskyrmions confirmed

Dependence on device thickness, field, and temperature analyzed

Link between antiskyrmions and complex magnetic interactions established

Abstract

Skyrmionic materials hold the potential for future information technologies, such as racetrack memories. Key to that advancement are systems that exhibit high tunability and scalability, with stored information being easy to read and write by means of all-electrical techniques. Topological magnetic excitations such as skyrmions and antiskyrmions, give rise to a characteristic topological Hall effect. However, the electrical detection of antiskyrmions, in both thin films and bulk samples has been challenging to date. Here, we apply magneto-optical microscopy combined with electrical transport to explore the antiskyrmion phase as it emerges in crystalline mesoscale structures of the Heusler magnet Mn$_{1.4}$PtSn. We reveal the Hall signature of antiskyrmions in line with our theoretical model, comprising anomalous and topological components. We examine its dependence on the vertical device thickness, field orientation, and temperature. Our atomistic simulations and experimental anisotropy studies demonstrate the link between antiskyrmions and a complex magnetism that consists of competing ferromagnetic, antiferromagnetic, and chiral exchange interactions, not captured by micromagnetic simulations.