Cluster growth through evaporation processes.

Abstract

A new cluster-growth model in which all surface sites (tip particles) of immobile clusters can evaporate with equal probability and diffuse until they stick to other clusters has been proposed and studied by using Monto Carlo simulations. This model is a multicluster version of the Botet-Jullien (BJ) model [Botet and Jullien, Phys. Rev. Lett. 55, 1943 (1985)]; particles, initially dispersed at random and later evaporated from clusters, random-walk and stick upon collision to other particles or clusters to form larger clusters. The cluster-size distribution ${n}_{s}$(t), which is the number of clusters of size s at time t, can be well represented by the dynamic scaling form ${n}_{s}$(t)\ensuremath{\sim}${s}^{\mathrm{\ensuremath{-}}2}$f(s/${t}^{z}$), where z\ensuremath{\simeq}(1/2 in the two-dimensional case and in one dimension z\ensuremath{\simeq}(1/3. Moreover, the size and form of each cluster are found to fluctuate drastically throughout the growth, giving rise to the 1/f-like spectra of fluctuations of total number of the tip particles.