Strain-engineering of magnetic coupling in two-dimensional magnetic semiconductor CrSiTe3: Competition of direct exchange interaction and superexchange interaction

•The monolayer CrSiTe3 is an intrinsic ferromagnetic semiconductor.•Ferromagnetic stability can be enhanced largely by applying a tensile strain.•The tensile strain of 8% can enhance the Curie temperature to 290 K.•The mechanism is the competition effect of two kinds of exchange interaction.

In this paper, we demonstrate by the density functional theory calculations that the monolayer CrSiTe3 is an intrinsic ferromagnetic semiconductor. More importantly, ferromagnetic stability can be enhanced significantly by applying an elastic tensile stain, implying their potential applications in spintronic devices at room temperature. In addition, a ferromagnetic–antiferromagnetic transition occurs under the small compression stain. The underlying physical mechanism is attributed to a competition effect of direct antiferromagnetic interaction and indirect ferromagnetic superexchange interaction.