A model of surface growth given by a two-dimensional discrete, driven, damped sine-Gordon equation is studied using Langevin dynamics. Our large-scale simulations show that the equilibrium Kosterlitz-Thouless roughening transition splits into two crossovers (or transitions) under the external force of, e.g., vapor-surface chemical potential difference. Three different regimes are characterized in terms of roughness, growth rate, and height-height correlations-the onset of a rough phase is accompanied by the suppression of oscillatory growth. Our results are interpreted consistently within a renormalization-group framework. We discuss the generality of our conclusions and propose specific comparisons with experiments.
ASJC Scopus subject areas
- Condensed Matter Physics