Interface ferromagnetism and anomalous Hall effect of CdO/ferromagnetic insulator heterostructures

TL;DR

This paper reports the experimental discovery of interface ferromagnetism and anomalous Hall effect in CdO/ferromagnetic insulator heterostructures, advancing the understanding of oxide interfaces for quantum anomalous Hall effect applications.

Contribution

It demonstrates the realization of interfacial ferromagnetism and anomalous Hall effect in Fe3O4/CdO heterostructures, highlighting the role of interface states in these phenomena.

Findings

Interface ferromagnetism observed in heterostructures.

Anomalous Hall effect linked to interface states.

CdO thickness influences magnetic and transport properties.

Abstract

The experimental observation of quantum anomalous Hall effect (QAHE) in magnetic topological insulators has stimulated enormous interest in condensed-matter physics and materials science. For the purpose of realizing high-temperature QAHE, several material candidates have been proposed, among which the interface states in the CdO/ferromagnetic insulator heterostructures are particularly interesting and favorable for technological applications. Here, we report the experimental observation of the interfacial ferromagnetism and anomalous Hall effect in the Fe3O4/CdO/Fe3O4 heterostructures grown via oxide molecular-beam epitaxy. Systematical variation of the CdO thickness reveals the interface ferromagnetism as the major cause for the observed planar magnetoresistance and anomalous Hall effect. Our results might pave the way to engineer oxide interface states for the exploration of QAHE towards exotic quantum-physical phenomena and potential applications.