Step bunching induced by flow in solution

By carrying out Monte Carlo simulations, we study step bunching induced by flow in solution during dissolving. For simplicity, we assume that steps are straight and express an array of steps as dots on one-dimensional vicinal face. We consider a two square lattice to represent the diffusion field in a solution. The diffusion of atoms in a solution is expressed as the hopping of atoms on lattice sites. During dissolving, the step bunching occurs in the case of step-up flow. In an early stage, the width of the fluctuation of step distance, w, increases with time as tα. The exponent α is equal to 12 in the initial stage. Then, α decreases and is approximately given by 14. In a late stage, the width w is saturated. The saturated value of w increases with the strength of flow.