The intrinsic ferromagnetic half-metals with high Curie temperature of tetragonal XCrS4 (X=Ti, Zr) monolayer

Two-dimensional intrinsic magnetic materials with a high Curie temperature (T-C) and 100% spin-polarization are highly desirable for creating spintronic devices. In this work, the electronic structure and intrinsic magnetism of XCrS4 (X = Ti, Zr) monolayers are predicted by using first-principles calculations. XCrS4 (X = Ti, Zr) monolayer materials exhibit excellent dynamical, thermal, and dynamically stable stability and small binding energy. The band structures show that XCrS4 (X = Ti, Zr) monolayers are intrinsic ferromagnetic (FM) half-metals with wide half-metallic gaps. Monte Carlo simulations based on the Heisenberg model are used to estimate the Curie temperature (T-C) of the TiCrS4 (73 K) and ZrCrS4 (216 K) monolayers. The magnetic performances can be significantly modulated by strain; the TiCrS4 monolayer can undergo FM to antiferromagnetic phase transition under certain uniaxial and biaxial strains. The results indicate that the intrinsic half-metals with higher T-C and controllable magnetic properties make XCrS4 (X = Ti, Zr) monolayers enrich the application of nanoscale spintronic devices.