Magnetocaloric Properties of Surface Effects in Perovskites Ferromagnetic Thin Films

The Monte Carlo simulations were used to study the surface effects on the magnetocaloric properties of ferromagnetic perovskite thin films. The thermal magnetization, transition temperatures, magnetic entropy change, relative cooling power, and magnetic hysteresis cycle temperature as a function of film thickness and exchange coupling were found. of surface. The reduced critical temperature of perovskite ferromagnetic thin films is studied as a function of the film thickness and the exchange interactions in the bulk, in the surface and between the surfaces. We have shown that the maximum entropy change in thin-film systems can be observed at temperatures well below the magnetic phase transition temperature. Maximum entropy changes increase with increasing external magnetic field. The relative cooling power increases with increasing external magnetic field and depends on the film thickness. The relative cooling power decreases with increasing surface exchange coupling value. The magnetic coercive field decreases with increasing temperature values when the surface exchange coupling is lower than the volume exchange coupling. The magnetic coercive field of perovskite ferromagnetic thin films is investigated as a function of reduced surface exchange coupling.