Monte Carlo simulations of the Blume–Emery–Griffiths model with S=3/2 and S=5/2

Abstract

The magnetic properties of the Blume–Emery–Griffiths(BEG) model [1] with fractional large spin(S=3/2 and S=5/2) on two-dimensional square lattice are discussed by making use of the Monte Carlo (MC) simulation for the magnetization 〈Sz〉, sublattice magnetizations 〈Sz(A)〉 and 〈Sz(B)〉, the magnetic specific heat CM and spin structures. The ground state phase diagram of these models has been obtained for exchange parameter J2/J1 and anisotropy parameter D/J1. The temperature dependence of sublattice magnetizations 〈Sz(A)〉 and 〈Sz(B)〉 is investigated for various values of the anisotropy D. The relations between the Curie temperature Tc and the critical temperature Ts at which sublattice magnetizations begin taking different values are also studied.