Strain-regulated magnetic phase transition and perpendicular magnetic anisotropy in CrSBr monolayer

Two-dimensional materials with intrinsic and large ferromagnetism have recently attracted extensive interests due to their promising potential for spintronic applications. Here, we systematically study the magnetic phase transition and anisotropy of monolayer CrSBr under different uniaxial strains using first-principles calculations. Our results show that the unstrained monolayer CrSBr is a ferromagnetic indirect band gap semiconductor with magnetic anisotropy along the a-axis. The magnetic transitions from ferromagnetic to antiferromagnetic order occur only when the compressive strain along the a-axis is increased to 11%. However, a perpendicular magnetic anisotropy of monolayer CrSBr can be driven by applying the 2% tensile strain along a-axis or 3.75% compressive strain along b-axis. Furthermore, as the tensile or compressive strains are continuously increased, the magnetic anisotropy energy can be significantly enhanced within ferromagnetic order due to the combining contribution and competition effect of the Cr-3d and Br-4p orbital. The tunable perpendicular magnetic anisotropy shows that monolayer CrSBr may be a promising candidate in spintronic devices.