Effect of surface orientation and thickness on the magnetization of anisotropic FCC ferromagnetic films

Abstract The dependence on temperature of the layer magnetization of a Heisenberg ferromagnetic ultrathin film in presence of magnetocrystalline single-ion anisotropy was theoretically investigated in the framework of a Green's function approach using the random phase approximation (RPA). The effect of surface orientation and of film thickness N on the Curie temperature TC was carefully investigated in the case of face centered cubic (FCC) films: the steepest increase of TC(N) was found in the case of the FCC(1 1 1) orientation and the smoothest in the FCC(1 1 0) one. Our results for TC(N) were successfully fitted by a finite-size scaling relation [TC(∞)−TC(N)]/TC(N)=(N/N0)−λ, giving a shift exponent λ≃1.5, irrespectively of the surface orientation. Finally, the temperature evolution of the magnetization profile was analyzed, as well as its limiting shape at TC.