Exchange interaction and magnetic phase transition in layered Fe/Au superlattices

In order to study the finite-temperature properties of the layered Fe/Au su perlattice, Monte Carlo (MC) simulations are carried out based on a Heisenb erg model with the exchange parameters extracted from the ab initio total e nergies and a phenomenological anisotropy constant. It is argued that the C urie temperature is rather insensitive to the anisotropy and is essentially determined by the ab initio exchange parameters. Due to the reduced coordi nation number of the magnetic atoms at interfaces, the Curie temperature ob tained by this ab initio-MC scheme decreases as decreasing of Fe layer thic kness is governed essentially by Weiss'law. (C) 2001 Elsevier Science B.V. All rights reserved.