Amazonas, M.S.; Cabral Neto, J.; Sousa, J. Ricardo de - In: Physica A: Statistical Mechanics and its Applications 331 (2004) 1, pp. 198-206
The dependence of the critical temperature Tc(ℓ,Δ) on film thickness ℓ and ratio of surface (Js) to bulk (Jb) exchange interaction strengths Δ≡(Js/Jb)−1 in quantum spin 12 Heisenberg model is studied by using the variational principle within the framework of the mean field...