Stacking- and strain-dependent magnetism in Janus CrSTe bilayer

Stacking order and strain are the key component in tuning magnetic property of two-dimensional (2D) van der Waals magnetic materials. In this work, we investigated the crystal structure stability of a 2D ferromagnetic Janus chromium dichalcogenide CrSTe bilayer in AB- and AC-stacking orders and found that AB-stacking CrSTe bilayers, which have a smaller layer spacing and a Curie temperature near room temperature, are more stable than AC-stacking one. The magnetic ground states, exchange coupling constant, and Curie temperature of the AB-stacking CrSTe bilayer can be tuned by strain. It is found that the magnetic ground states of the AB- and AC-stacking CrSTe bilayers are ferromagnetic and interlayer antiferromagnetic within a certain strain range, respectively, indicating that the CrSTe bilayers are expected to be used in the double spin filter. Our results demonstrated that the 2D Janus CrSTe bilayer has the potential in the application of spintronic devices with stable performance and low-power consumption at room temperature.