Pressure driven magnetic phase change in CrI3/Br3Cr2I3 heterostructure

Abstract

The vertically stacked van der Waals (vdW) heterostructures provide a promising platform not only in the band alignment but also constitute a fertile ground for the fundamental science and tremendous practical interest towards different device applications. Beyond most two-dimensional (2D) materials being intrinsically non-magnetic, CrI3 is a novel material with vdW bonded layer dependent magnetism, promising the potential spintronics applications. However, for prominent device applications, heterostructure is commonly fabricated and it is necessary to examine the effect of the interface or contact atoms over the magnetic properties of the heterostructure. And most importantly, the effect of assembly stress on the electronic and magnetic properties remains not clear. In this study, we design a vdW heterostructure from the two-chromium tri-halides called CrI3/Br3Cr2I3 heterostructure, where the Janus of the CrI3 monolayer called Br3Cr2I3 is also an intrinsically 2D magnetic material. Using the state-of-the-art first principles calculations, we uncover the effects of contact atoms as well as external pressure over the electronic and magnetic properties of the CrI3/Br3Cr2I3 heterostructure. It is found that the heterostructure transits from antiferromagnetic (AFM) to ferromagnetic (FM) ground state with pressure larger than certain threshold. We also investigate the magneto-crystalline anisotropy energy (MAE) of the CrI3/Br3Cr2I3 heterostructure. Remarkably, it is found that the MAE is significantly influenced by both the stacking as well as the contact atoms, which is abruptly and inconsistently varying by the contact atoms and external pressure. Further, we also reveal the correlation between MAE and the polar angle. The pressure regulated magnetic properties of the CrI3/Br3Cr2I3 heterostructures as revealed in this study highlight its potential applications for spintronic applications devices.