title: Ordering in random overlayers: the correlated cluster mean-field method.
abstract: We have extended a recently proposed correlated cluster mean-field (CCMF) theory to two-dimensional binary alloys with interactions up to the next-nearest neighbors and investigated their critical behavior. A very good agreement with results from the renormalization group theory was obtained for the critical temperatures of a simple model. We finally successfully compared our results obtained using the CCMF with the results of Monte Carlo simulations for the case of ordering in a random Fe(0.5)Co(0.5) overlayer on the Cu(001) substrate. The proposed theory represents a numerically efficient alternative to existing approaches like the cluster variation method and Monte Carlo simulations.
authors.affiliation: Institute of Physics, AS CR, v.v.i., Na Slovance 2, 182 21 Prague 8, Czech Republic.
authors.forename: Z
authors.initials: Z
authors.lastname: Chvoj
authors.forename: J
authors.initials: J
authors.lastname: Kudrnovský
authors.forename: V
authors.initials: V
authors.lastname: Drchal