Critical Behavior of a 2D Spin-Pseudospin Model in a Strong Exchange Limit

Abstract

We study the 2D static spin-pseudospin model equivalent to the dilute frustrated antiferromagnetic Ising model with charge impurities. We present the results of classical Monte Carlo simulation on a square lattice with periodic boundary conditions in a “strong” exchange limit. In the framework of the finite-size scaling theory we obtained the static critical exponents for the specific heat α and the correlation length ν for a wide range of the local density–density interaction parameter ∆ and charge density n. It was shown that the system exhibits non-universal critical behavior depending on these parameters. © 2020 Polish Academy of Sciences. All rights reserved.