A first-principles and Monte Carlo study of a 2D cerium-based ferromagnetic semiconductor

Abstract Two-dimensional intrinsic ferromagnetic semiconductors hold significant promise for spintronic device applications. Here, using first principles calculations, we predict the properties of a novel rare-earth-based Cerium monolayer, namely CeI 2 . The thermodynamic, mechanical, and dynamical stability of the proposed monolayer are systematically studied, while band structure calculations demonstrate that it exhibits intrinsic ferromagnetic semiconducting behavior with an indirect band gap. The magnetism of this monolayer originates mainly from the Ce(f) orbitals and exhibits an in-plane easy axis along the [010] crystallographic direction. Monte Carlo simulations, based on the Heisenberg spin Hamiltonian, estimate the Curie temperature to be 318.9 K, demonstrating the potential of this monolayer for spintronics devices. Moreover, the effect of biaxial strain on the magnetic properties of the monolayer is investigated to explore its suitability for flexible devices. Our findings show that the ferromagnetic state of the monolayer is maintained only for a strain range between ±1%. In addition, we show that strain has a considerable impact on both the magnetic anisotropy energy (MAE) and the transition temperature.