Exchange bias and spin-orbit torque in the Fe3GeTe2-based heterostructures prepared by vacuum exfoliation approach

Magnetic two-dimensional (2D) van der Waals (vdWs) materials are receiving increased attention due to their exceptional properties and potential applications in spintronic devices. Because exchange bias and spin-orbit torque (SOT)-driven magnetization switching are basic ingredients for spintronic devices, it is of pivotal importance to demonstrate these effects in the 2D vdWs material-based magnetic heterostructures. In this work, we employ a vacuum exfoliation approach to fabricate Fe3GeTe2 (FGT)/Ir22Mn78 (IrMn) and FGT/Pt bilayers, which have high-quality interfaces. An out-of-plane exchange bias of up to 895Oe is obtained in the former bilayer, which is larger than that of the previously studied bilayers. In the latter bilayer, the SOT switching of the perpendicularly magnetized FGT is realized, which exhibits higher SOT-driven switching performance compared to the previously studied FGT/Pt bilayer devices with interfacial oxidation. The minimum of SOT efficiency is further determined to be 0.18 +/- 0.04, comparable to the previously reported values for the Pt/Co and Pt/CoFeB bilayers. This work highlights the importance of the high-quality interface for the exchange bias and SOT effect and may pave the way for implementing 2D vdWs in spintronic devices.

Automated summary

This study demonstrates the importance of high-quality interfaces in achieving exchange bias and SOT effect in 2D van der Waals materials-based magnetic heterostructures. The results show significant out-of-plane exchange bias and improved SOT-driven switching performance, paving the way for the implementation of 2D van der Waals materials in spintronic devices.