Enhanced Curie temperature in partially decorated CrSnSe₃ monolayer with alkali metals (Li, Na, and K)

A two-dimensional ferromagnetic layer with a large Curie temperature is highly desired for spintronics applications. Herein, we investigated the effect of the partial decoration of the CrSnSe₃ monolayer with alkali metals Li, Na, and K on the structure, electronic and magnetic properties. The calculated formation energy, phonon dispersion curves, and ab initio molecular dynamics indicated that the decorated CrSnSe₃ layers are stable and can be fabricated. The Li, Na, and K decorated systems display semiconducting band features, with bandgaps of 0.53, 0.55, and 0.55 eV, respectively, with the HSE06 hybrid functional. We found a ferromagnetic ground state and an in-plane magnetic anisotropy of -2.12, -2.42, and -2.39 meV per cell in the Li, Na, and K-decorated systems, respectively. Based on Monte Carlo Simulations, we obtained largely enhanced Curie temperatures of 241, 256, and 265 K in the Li, Na, and K decorated systems, respectively. Our findings suggest that the decorated layers could be used as potential candidates for spintronics applications.