Magnetite thin films: A simulational approach

摘要

In the present work the study of the magnetic properties of magnetite thin films is addressed by means of the Monte Carlo method and the Ising model. We simulate L x L x d magnetite thin films (d being the film thickness and L the transversal linear dimension) with periodic boundary conditions along transversal directions and free boundary conditions along d direction. In our model, both the three-dimensional inverse spinel structure and the interactions scheme involving tetrahedral and octahedral sites have been considered in a realistic way. Results reveal a power-law dependence of the critical temperature with the film thickness accordingly by an exponent v = 0.81 and ruled out by finite-size scaling theory. Estimates for the critical exponents of the magnetization and the specific heat are finally presented and discussed. (c) 2006 Elsevier B.V. All rights reserved.