A Combined Model and Its Verification for Femtosecond-Pulse Materials Interactions

This paper reports the overall picture of our ongoing efforts to establish the scientific understanding of ultrafast, non-equilibrium laser-material interactions from nanometer to milimeter and from femtosecond to microsecond through comprehensive, integrated multiscale physico-chemical modeling and experimental verification. A novel plasma model with quantum treatments is developed to account for significantly varying optical properties. The model is used to successfully predict two uncommon phenomena that is experimentally observed: 1) a flat-bottom crater shape created by a Gaussian beam and 2) repeatable nanoscale structures achieved by pulse train technology. The well known two-temperature model is improved by considering the quantum effects of different heat carriers and then is used to accurately predict the damage thresholds for metals. Preliminary results for these ongoing modeling efforts are reported in this article.