The Mixed Spin-1 and Spin-5/2 BEG Model in a Staggered Magnetic Field

Abstract

The mixed spin-1 and spin- 2 Ising model with bilinear (J) and biquadratic (K) nearest-neighbor exchange interac- tions and a single-ion potential or crystal-field interaction (D) is investigated by means of recursion relations on the Bethe lattice in the presence of a staggered magnetic field. The interactions are assumed to be only between nearest- neighbors. The competition between model parameters leads to very rich T=0 phase diagrams which may be useful to explore interesting domains of the finite-temperature phase diagrams of the model. Some thermal properties of the system are presented. The magnetization is also described by numerical simulations of the model on a square lattice using Glauber stochastic dynamics in the presence of an oscillating external staggered field. Our present results bear little resemblance to those previously reported on various kinetic Ising systems obtained by integrating differential equations.