An introduced effective-field theory study of spin-1 transverse Ising model with crystal field anisotropy in a longitudinal magnetic field

TL;DR

This paper uses an effective-field theory to analyze the thermodynamic and magnetic properties of a spin-1 transverse Ising model with crystal field anisotropy and magnetic fields, revealing complex phenomena like reentrance.

Contribution

It introduces an improved effective-field approximation that accounts for spin correlations in the spin-1 transverse Ising model with crystal field and magnetic fields.

Findings

Reentrant phase transitions observed as functions of temperature and fields.

Calculated order parameters, free energy, and entropy showing complex behaviors.

Identification of effects of crystal field and magnetic fields on phase diagrams.

Abstract

A spin-1 transverse Ising model with longitudinal crystal field in a longitudinal magnetic field is examined by introducing an effective field approximation (IEFT) which includes the correlations between different spins that emerge when expanding the identities. The effects of the crystal field as well as the transverse and longitudinal magnetic fields on the thermal and magnetic properties of the spin system are discussed in detail. The order parameters, Helmholtz free energy and entropy curves are calculated numerically as functions of the temperature and Hamiltonian parameters. A number of interesting phenomena such as reentrant phenomena originating from the temperature, crystal field, transverse and longitudinal magnetic fields have been found.