Branco, N.S.; Chame, Anna - In: Physica A: Statistical Mechanics and its Applications 232 (1996) 1, pp. 487-498
We obtain bulk and surface order parameters of the spin-12 anisotropic Heisenberg ferromagnet in a semi-infinite (d = 3) lattice, as functions of the temperature. This model is described by the Hamiltonian −β H = Σ〈i,j〉Kij[(1 − Δij)(σixσjx + σiyσiy) + σizσjz], where the coupling...