Exchange bias between van der Waals materials: tilted magnetic states and field-free spin-orbit-torque switching

TL;DR

This study demonstrates how van der Waals heterostructures with exchange bias enable tilted magnetic states and field-free spin-orbit-torque switching, advancing 2D spintronics applications.

Contribution

It reveals the exchange bias mechanism in CrSBr/Fe3GeTe2 heterostructures and its role in enabling deterministic, field-free spin-orbit-torque switching in 2D materials.

Findings

Exchange bias from CrSBr induces tilted magnetic states in FGT.

In-plane exchange bias allows deterministic spin-orbit torque switching.

A minimum CrSBr thickness of >10 nm is required for non-zero exchange bias at 30 K.

Abstract

Magnetic van der Waals heterostructures provide a unique platform to study magnetism and spintronics device concepts in the two-dimensional limit. Here, we report studies of exchange bias from the van der Waals antiferromagnet CrSBr acting on the van der Waals ferromagnet Fe3GeTe2 (FGT). The orientation of the exchange bias is along the in-plane easy axis of CrSBr, perpendicular to the out-of-plane anisotropy of the FGT, inducing a strongly tilted magnetic configuration in the FGT. Furthermore, the in-plane exchange bias provides sufficient symmetry breaking to allow deterministic spin-orbit torque switching of the FGT in CrSBr/FGT/Pt samples at zero applied magnetic field. A minimum thickness of the CrSBr greater than 10 nm is needed to provide a non-zero exchange bias at 30 K.