CONTRASTS BETWEEN COARSENING AND RELAXATIONAL DYNAMICS OF SURFACES

We discuss static and dynamic fluctuations of domain walls separating areas of constant but different slopes in steady-state configurations of crystalline surfaces both by an analytic treatment of the appropria te Langevin equation and by numerical simulations. In contrast to othe r situations that describe the dynamics in Ising-like systems such as models A and B, we find that the dynamic exponent z = 2 that governs t he domain wall relaxation function is not equal to the inverse of the exponent n approximate to 1/4 that describes the coarsening process th at leads to the steady state.