Author(s)

S.George & K.Mitra

Abstract

This paper discusses the ablation phenomena in absorbing dielectrics due to ultra short pulses for potential applications in the field of material processing. The numerical model is based on multi-photon absorption followed by thermal degradation and diffusion. The wave nature of the propagating laser source, which has a temporal Gaussian distribution, is incorporated by considering the transient radiative transport equation. The mathematical formulation takes into consideration the saturation effects within the framework of two or three level systems of the electronic structure of chromophores. This involves solving a set of coupled rate equations, heat diffusion equation, and the transient radiative transport equation using two different schemes - a fully implicit iterative technique and a predictor corrector techn

Keywords