Multiscale kinetic Monte Carlo algorithm for simulating epitaxial growth

We present a fast Monte Carlo algorithm for simulating epitaxial surface growth, based on the continuous-time Monte Carlo algorithm of Bortz, Kalos, and Lebowitz. When simulating realistic growth regimes, much computational time is consumed by the relatively fast dynamics of the adatoms. Continuum and continuum-discrete hybrid methods have been developed to approach this issue; however, in many situations, the density of adatoms is too low to efficiently and accurately simulate as a continuum. To solve the problem of fast adatom dynamics, we allow adatoms to take larger steps, effectively reducing the number of transitions required. We achieve nearly a factor of ten speed up, for growth at moderate temperatures and large D/F.