Histogram Monte Carlo study of next-nearest-neighbor Ising antiferromagnet on a stacked triangular lattice

TL;DR

This study uses histogram Monte Carlo simulations to analyze the critical behavior of a stacked triangular lattice Ising antiferromagnet with competing interactions, revealing a transition in the XY universality class contrary to earlier mean-field predictions.

Contribution

It provides the first detailed Monte Carlo analysis of the critical properties of this specific frustrated Ising model, clarifying its universality class.

Findings

Transition remains in the XY universality class

Contradicts previous mean-field tricritical behavior suggestion

Supports recent phase diagram determinations

Abstract

Critical properties of the Ising model on a stacked triangular lattice, with antiferromagnetic first and second-neighbor in-plane interactions, are studied by extensive histogram Monte Carlo simulations. The results, in conjunction with the recently determined phase diagram, strongly suggest that the transition from the period-3 ordered state to the paramagnetic phase remains in the xy universality class. This conclusion is in contrast with a previous suggestion of mean-field tricritical behavior.