Theoretical aspects of laser-induced periodic surface structure formation

Laser-induced periodic pattern formation has been observed on a variety of substances. In particular, low-power laser have been used to deposit a pattern on a metal surface. For a relatively smooth surface grating, this pattern can be explained in terms of a perturbative solution of Maxwell's equations. However, as the surface grating is enhanced by this initial deposition, the perturbation solution breaks down. An alternate non-perturbative solution of Maxwell's equations for such rough surfaces is considered here. Moreover, other possible mechanisms that may assist pattern formation are discussed, such as field-enhanced evaporation and surface migration.