Critical behavior of the spin-$1/2$ Baxter-Wu model: Entropic sampling simulations

TL;DR

This study employs an advanced entropic sampling method to accurately determine the critical behavior and exponents of the spin-1/2 Baxter-Wu model, achieving results closely matching exact values.

Contribution

It introduces a refined Wang-Landau based entropic sampling technique to precisely analyze the critical properties of the Baxter-Wu model.

Findings

Critical exponents closely match exact values

High-precision estimate of critical temperature

Excellent agreement in microcanonical inverse temperature coefficients

Abstract

In this work we use a refined entropic sampling technique based on the Wang-Landau method to study the spin-$1/2$ Baxter-Wu model. The static critical exponents were determined as $\alpha=0.6545(68)$, $\beta=0.0818(30)$, $\gamma=1.18193(77)$, and $\nu=0.66341(47)$. The estimate for the critical temperature was $T_c=2.269194(45)$. We compare the present results with those obtained from other well established approaches and we find a startling closeness with the exact values, besides the high precision reached for the critical temperature. We also calculate the coefficients $a$ and $b$ for the divergence of the microcanonical inverse temperature at the ground state achieving an excellent agreement in comparison with the simulation estimates.