Multilayer transition in a spin 3/2 Blume–Capel model with RKKY interaction

Abstract

Using Monte Carlo simulation and mean-field theory, we have studied the effect of RKKY interaction on the multi-layer transition and magnetic properties of a spin-3/2 Blume–Capel model of a system formed by two magnetic multi-layer materials, of different thicknesses, separated by a non-magnetic spacer of thickness M . It is found that the multi-layer magnetic order–disorder transition temperature depends strongly on the thicknesses of the magnetic layer and the non-magnetic layer. The transition temperature increases with increasing thickness of the magnetic multi-layers and decreases with increasing thickness of the non-magnetic one. Furthermore, there exists a critical thickness M L of the non-magnetic spacer beyond which the effect of the RKKY interaction becomes negligible and separate transitions occur in the two magnetic layers. The critical thickness M L decreases on increasing the magnetic crystal field and/or the Fermi level k f . Moreover, the multi-layer transition temperature undergoes oscillations as a function of the Fermi level. The susceptibility critical exponents are computed within Monte Carlo simulations.