Ferromagnetism in MnX2 (X = S, Se) monolayers

Abstract

Using density functional theory combined with Monte Carlo (MC) simulations, we show that the two dimensional (2D) MnS₂ and MnSe₂ sheets are ideal magnetic semiconductors with long-range magnetic ordering and high magnetic moments (3 μ_B per unit cell), where all the Mn atoms are ferromagnetically coupled, and the Curie temperatures (T_C) estimated for MnS₂ and MnSe₂ by the MC simulations are 225 and 250 K, respectively, which can be further increased to 330 K and 375 K by applying 5% biaxial tensile strains.