Abstract:
The problem of metal surface instability under the influence of laser plasma in the process of nanosecond laser ablation in vacuum has been considered. To solve the problem, a numerical model of the Langmuir layer is constructed, which is applicable for calculations in the case when the layer thickness is much smaller than the characteristic wavelength of the melt surface perturbation. Analysis of the calculation results allowed us to find linear approximations of the ion pressure and electric field distributions on the metal surface. The use of these approximations allowed us to obtain an analytical criterion for the transition of the surface into an unstable state. It is also shown that the influence of the Langmuir layer leads to a decrease in the action of capillary forces, which can be used to modify the criteria for the development of instability in other mechanisms.