Spin glass behavior in a random Coulomb antiferromagnet

TL;DR

This study investigates spin glass behavior in a two- and three-dimensional random Coulomb antiferromagnet using Monte Carlo simulations, revealing a zero-temperature transition in 2D and weak evidence for a finite-temperature transition in 3D.

Contribution

First detailed Monte Carlo analysis of Coulomb antiferromagnets showing potential differences from traditional spin glass models.

Findings

2D transition at zero temperature with Edwards-Anderson-like exponents

Weak evidence for finite-temperature transition in 3D

Possible different universality class or critical dimension

Abstract

We study spin glass behavior in a random Ising Coulomb antiferromagnet in two and three dimensions using Monte Carlo simulations. In two dimensions, we find a transition at zero temperature with critical exponents consistent with those of the Edwards Anderson model, though with large uncertainties. In three dimensions, evidence for a finite-temperature transition, as occurs in the Edwards-Anderson model, is rather weak. This may indicate that the sizes are too small to probe the asymptotic critical behavior, or possibly that the universality class is different from that of the Edwards-Anderson model and has a lower critical dimension equal to three.