Critical behavior of the three-dimensional compressible Ising antiferroma gnet at constant volume: a Monte Carlo study

TL;DR

This study uses Monte Carlo simulations to investigate the critical behavior of a 3D compressible antiferromagnetic Ising model at constant volume, finding it aligns with the standard 3D Ising universality class despite theoretical expectations.

Contribution

First Monte Carlo analysis of a compressible 3D antiferromagnetic Ising model showing universality class consistency with the rigid model.

Findings

System remains in the 3D Ising universality class.

Elastic forces do not alter the critical universality class.

Results contrast with some theoretical predictions.

Abstract

Extensive Monte Carlo simulations in the semi-grand-canonical ensemble are used to study the critical behavior of a three-dimensional compressible Ising model with antiferromagnetic interactions under constant volume conditions. Elastic forces between spins are introduced by the Stillinger-Weber potential and energy parameters are chosen in such a way that antiparallel spin ordering is favored, analogous to the antiferromagnetic coupling in the rigid Ising Hamiltonian. All the quantities analyzed strongly indicate that the system remains in the universality class of the standard (rigid) three-dimensional Ising model, in contrast with theoretical predictions.