Critical properties of the frustrated Ising model on a honeycomb lattice: A Monte Carlo study

TL;DR

This study uses Monte Carlo simulations to explore the critical and dynamical properties of the frustrated $J_1-J_2$ Ising model on a honeycomb lattice, revealing phase transition behaviors and challenges in analyzing highly frustrated regimes.

Contribution

It provides the first detailed Monte Carlo analysis of the phase boundary and critical behavior of the $J_1-J_2$ Ising model on a honeycomb lattice, especially in the highly frustrated regime.

Findings

Phase transition remains second-order for R ≥ -0.2.

Transition follows the standard Ising universality class.

Highly frustrated regime exhibits slow dynamics and metastable states.

Abstract

Critical and in the highly frustrated regime also dynamical properties of the $J_1-J_2$ Ising model with competing nearest-neighbor $J_1$ and second-nearest-neighbor $J_2$ interactions on a honeycomb lattice are investigated by standard Monte Carlo and parallel tempering simulations. The phase boundary is determined as a function of the coupling ratio for the phase transition between the paramagnetic and ferromagnetic states within $R \equiv J_2/|J_1| \in [-1/4,0]$. It is confirmed that at least for $R \geq -0.2$ the transition remains second-order and complies with the standard Ising universality class. In the highly frustrated regime of $R < -0.2$ and low temperatures the system tends to freeze to metastable domain states, separated by large energy barriers, which show extremely sluggish dynamics. The resulting huge equilibration and autocorrelation times hinder the analysis of critical properties and thus the character of the transition in this region remains to be determined.