We have simulated, by using a cluster algorithm, the $q=8\mathrm{}$ state Potts model in two dimensions with a varying amount of quenched bond randomness. We have shown that there exists a finite size-dependent threshold value of the introduced quenched bond randomness for rounding the first-order phase transition and that this threshold value becomes smaller as the system size increases.

• Received 3 April 1998

DOI:https://doi.org/10.1103/PhysRevE.58.4210