Correlations and Coarsening in the q-State Potts Model
Résumé
We study the nonequilibrium dynamics of the q-state Potts model following a quench from the high-temperature disordered phase to zero temperature. We calculate, within a Gaussian closure approximation, the time-dependent two-point correlation functions for general q. These correlation functions obey dynamic scaling with a length scale L(t)∼t1/2, while the autocorrelation function decays as L(t)-λ(q). We also establish a correspondence of this model to the Ising model evolving with a fixed magnetization (2/q-1). Extensive numerical simulations of the Potts model in two dimensions show good agreement with our theory.