Mesoscopic description of step dynamics on crystal surfaces

Steps are long-lived structural defects on crystal surfaces, and as such they constitute a natural basis for the description of surface morphology and dynamics on mesoscopic scales. The step dynamical approach plays a pivotal role in any multiscaling scheme for crystal surface evolution, because it can be connected in a quantitative and rigorous fashion both to atomistic methods such as kinetic Monte Carlo simulations, and to large scale continuum height representations of the global surface morphology. Both connections will be illustrated in the talk, using as examples our recent work on step bunching instabilities and island electromigration.