FRACTAL INTERFACES IN HETEROGENEOUS EDEN-LIKE GROWTH

We perform computer simulations of Eden-like growth models in two dimensions with random reactions that either allow or inhibit further growth. By varying the probabilities of such reactions, the cluster develops a variety of fractal interfaces related to the hull and the external perimeter of the usual percolation cluster. However, a blocking mechanism leads to different fractal dimensions. Reaction probabilities away from the critical value were also found to give different effective dimensions due to slow crossovers. These results may explain the nonuniversal surface roughness observed in heterogeneous materials.