Random-bond Potts model in the large-q limit - art. no. 056122

We study the critical behavior of the q-state Potts model with random ferro magnetic couplings. Working with the cluster representation the partition s um of the model in the large-q limit is dominated by a single graph, the fr actal properties of which are related to the critical singularities of the random-Potts model. The optimization problem of finding the dominant graph, is studied on the square lattice by simulated annealing and by a combinato rial algorithm. Critical exponents of the magnetization and the correlation length are estimated and conformal predictions are compared with numerical results.