Current-induced magnetization switching in a magnetic topological insulator heterostructure

TL;DR

This paper demonstrates current-induced magnetization switching in a magnetic topological insulator heterostructure, highlighting the role of spin-orbit torque and its potential for spintronic applications.

Contribution

It introduces a method to control magnetization direction via bias current in a topological insulator heterostructure, advancing spintronic device technology.

Findings

Current bias affects coercive field and magnetic order.

Magnetic moments can be reoriented by current and external magnetic field.

Reversal of spin polarization and chiral edge mode observed.

Abstract

We present the current-induced switching of the internal magnetization direction in a magnetic topological insulator/topological insulator heterostructure in the quantum anomalous Hall regime. The switching process is based on the bias current dependence of the coercive field, which is attributed to the effect of the spin-orbit torque provided by the unpolarized bias current. Increasing the bias current leads to a decrease in the magnetic order in the sample. When the applied current is subsequently reduced, the magnetic moments align with an externally applied magnetic field, resulting in repolarization in the opposite direction. This includes a reversal of the spin polarisation and hence a reversal of the chiral edge mode. Possible applications in spintronic devices are discussed.