Magnetic–Electronic Coupling in the Strained Bilayer CrSBr

Recently, van der Waals layered-magnetic CrSBr has been successfully synthesized and has drawn a great amount of attention. CrSBr crystallizes in the orthorhombic symmetry group and exhibits triaxial magnetic anisotropy, which shows a strong potential for modulation. By first-principles and Monte Carlo simulations, we investigated the magnetic properties of bilayer CrSBr. We find that bilayer CrSBr tends to have different magnetic orders by altering the stacking modes. Under biaxial strain, the dislocatedly stacked bilayer CrSBr can transform from an antiferromagnetic (AFM) state to a ferromagnetic (FM) state when the biaxial compressive strain reaches −2%. As a triaxial magnetic anisotropy material, the hard magnetization axis of bilayer CrSBr changes from the x-axis to the z-axis under a compressive biaxial strain of 4% for directly stacked CrSBr. Furthermore, the magnetic-electronic coupling can affect the distribution of the spin-excitons in real space. In the FM state, the spin-up excitons are widely distributed in both the top and bottom layers. While in the AFM state, the spin-up excitons can be excited only in the bottom layer and the spin-down excitons can be excited solely in the top layer. Therefore, the distribution of the spin-excitons is coupled to the magnetic order. Based on magnetic–electronic coupling, the distribution of the spin-excitons can be modulated by either applying biaxial strain or changing the stacking modes in bilayer CrSBr.