Phase transition in compressible Ising systems at fixed volume

TL;DR

This paper investigates the phase transition behavior of compressible Ising systems at fixed volume using a Ginzburg-Landau model, revealing coexistence regions, a field-induced critical point, and phase ordering phenomena.

Contribution

It introduces a detailed analysis of phase coexistence and criticality in compressible Ising systems at constant volume, highlighting the role of temperature and magnetic field.

Findings

Coexistence of two phases within a specific T-h region.

Identification of a field-induced critical point with diverging correlation length.

Numerical investigation of phase ordering dynamics.

Abstract

Using a Ginzburg-Landau model, we study the phase transition behavior of compressible Ising systems at constant volume by varying the temperature $T$ and the applied magnetic field $h$. We show that two phases can coexist macroscopically in equilibrium within a closed region in the $T$-$h$ plane. It occurence is favored near tricriticality. We find a field-induced critical point, where the correlation length diverges, the difference of the coexisting two phases and the surface tension vanish, but the isothermal magnetic susceptibility does not diverge in the mean field theory. We also investigate phase ordering numerically.