An introduced effective-field approximation and Monte Carlo study of a spin-1 Blume–Capel model on a square lattice

Abstract

The magnetic properties of a spin-1 Blume–Capel (BC) model on a square lattice (q=4) with a ferromagnetic interaction have been examined here by the use of Monte Carlo (MC) simulation technique and an introduced effective-field approximation (IEFT), which includes the correlations between different spins that emerge when expanding the identities. The effects of the external magnetic field and crystal field on the magnetic properties of the spin system are discussed in detail. In order to obtain credible results, a detailed comparison of the results obtained by the two methods has been made with those of the other methods in the literature. A number of interesting phenomena originating from the temperature, crystal field and external field have been found.