The Temperature Dependent Anisotropy Influence on the Magnetic Behavior of Thin Films

The magnetism of the layered materials attracts a great interest in the last years. In this context, it is necessary to take into account the anisotropic comportment of this kind of systems, due to its important influence on the magnetic properties that characterize these structures. In this paper, we intend to study in a numerical manner the effect of the temperature dependence of the anisotropic parameters on the specific behavior of a two-dimensional square lattice of unitary magnetic spins. Thus, using the Monte Carlo technique, we calculate the magnetic susceptibility and the specific heat of the considered physical system governed by a Heisenberg type Hamiltonian and we determine the magnetic properties of the system, induced by the temperature dependence of anisotropy that characterizes the thin film. In this context, we point out a slow decrease of the critical temperature specific to the ferromagnetism-paramagnetism phase transition, in comparison with the case of constant anisotropy. We also detect a critical temperature slight decrease along with the increasing slope of the anisotropy linear variation as a function of temperature.