Multiscaling of energy correlations in the random-bond Potts model

TL;DR

This paper numerically investigates energy correlation decay in the random-bond Potts model, confirming theoretical predictions and providing insights into disorder effects and replica symmetry.

Contribution

It provides the first numerical calculation of energy correlation exponents in the q-state random-bond Potts model, supporting perturbative renormalization group results.

Findings

Results agree with two-loop expansion predictions.

Fulfills the correlation length bound    2/d.

Provides evidence against replica symmetry breaking.

Abstract

We numerically calculate the exponent for the disorder averaged and fixed-sample decay of the energy-energy correlator in the q-state random-bond Potts model. Our results are in good agreement with a two-loop expansion (cond-mat/9910181) around q=2 recently found from perturbative renormalisation group techniques, fulfill the correlation length bound \nu >= 2/d, and give further evidence against replica symmetry breaking in this class of models.