Two-Dimensional 8-State Potts Model on Random Lattices: A Monte Carlo Study

We use two-dimensional Poissonian random lattices of Voronoi/ Delaunay type to study the effect of quenched coordination number randomness on the nature of the phase transition in the eight-state Potts model, which is of first order on regular lattices. From extensive Monte Carlo simulations we obtain strong evidence that the phase transition remains first order for this type of quenched randomness. Our result is in striking contrast to a recent Monte Carlo study of quenched bond randomness for which the order of the phase transition changes from first to second order.