Effects of step–step interactions on the fluctuations of an individual step on a vicinal surface and its wavelength dependence

We relate properties of an anisotropic continuum model of a two-dimensional vicinal surface to those of a model with fluctuating and interacting steps. We show that analysis of the fluctuations of an individual step in the array provides information about the length scale on which the surface has reached equilibrium and can be used to estimate fundamental step parameters from locally equilibrated surfaces. Monte Carlo simulations of a stable vicinal surface using the terrace–step–kink model agree with the theoretical predictions. We further apply this analysis to steps on an unstable surface during reconstruction-induced faceting and show that it can be used to determine whether the faceting process is in the nucleation or spinodal decomposition regime. © 1999 Elsevier Science B.V. All rights reserved.