Chromium sulfide halide monolayers: intrinsic ferromagnetic semiconductors with large spin polarization and high carrier mobility.

Two-dimensional (2D) ferromagnetic semiconductors (FMSs) are desirable for their potential to enhance the functionality of semiconductor devices via the utilization of spin degrees of freedom. Herein, we predict a series of intrinsic FMS monolayers in the chromium sulfide halide CrSX (X = Cl, Br, I) family with large spin polarization, large magnetic moments and high Curie temperatures. Such CrSCl and CrSBr monolayers also have high hole mobilities up to 6.6 × 103 and 5.3 × 103 cm2 V-1 s-1, respectively. Furthermore, these 2D monolayers exhibit excellent dynamic and thermal stabilities and a small exfoliation energy from the bulk. These intrinsic FMSs with their high mobilities may provide competitive candidates for next-generation spintronics and electronics.