Brownian motion and shape fluctuations of single-layer adatom and vacancy clusters on surfaces: Theory and simulations

Abstract

In recent observations of Brownian motion of islands of adsorbed atoms and of vacancies with mean radius R, the cluster diffusion constant Dc varies as R1 and R2. From an analytical continuum description of the cluster's steplike boundary, we find a single Langevin equation for the motion of the cluster boundary, rather than three special cases.