Topological Hall effect in a non-magnetic metal interfaced to a canted antiferromagnetic insulator in perovskite oxide heterostructures

TL;DR

This study demonstrates a topological Hall effect in a non-magnetic metal interfaced with a canted antiferromagnetic insulator in perovskite oxide heterostructures, revealing emergent fields from non-coplanar spin textures.

Contribution

It shows the universal emergence of topological Hall effect at heterointerfaces involving antiferromagnetic insulators and metals, expanding material options for emergent transport phenomena.

Findings

Observation of a 30 T effective magnetic field at 20 K.

Topological Hall effect attributed to non-coplanar spin textures.

Proximity-induced emergent fields are universal in heterointerfaces.

Abstract

We report interfacial transport properties in in-situ grown orthorhombic perovskite oxide heterostructures consisting of an antiferromagnetic insulator DyFeO$_3$ and a paramagnetic conductor CaRuO$_3$. We observe Hall effect with a step-like increase amounting to an effective magnetic field of 30 T at 20 K. We provide a plausible explanation in the context of topological Hall effect originating from a non-coplanar spin texture and resultant emergent field in DyFeO$_3$ associated with the scalar spin chirality. Our results demonstrate that the proximity effect of the emergent field at heterointerfaces is a universal physical phenomenon, while it has been reported originally in a heterointerface composed of pyrochlore oxides. This will greatly expand the choice of materials to the heterointerfaces for the research in emergent transport phenomena, which has been limited to single compounds with both metallic properties and special spin textures. Additionally, this will pave the way for possible device application of the emergent field by designing and combining perovskite oxides with versatile functionalities such as multiferroicity.