Ablation of opaque surfaces due to laser irradiation
The time-dependent ablation process of a metal surface due to laser irradiation is investigated for the case of high Peclet numbers. An analytical solution of the energy balance equation is found by the method of characteristics. The theory is restricted to the geometrical-optical approximation. There exist self-similar solutions which are piecewise parabolic in space. Their amplitude is damped which finally leads to a smoothed quasistationary surface profile. An expression for the decay time of this solution is derived which depends on the amplitude and the length of periodicity.