Transient scattering effects and electron plasma dynamics during ultrafast laser ablation of water.

Abstract

We study the dynamics of single-shot ultrafast laser ablation of a water-gas interface. We model the extremely nonlinear light-water interaction during the first picosecond by simulating the laser pulse propagation while dynamically calculating the spatial distribution of the dielectric function. We make use of a finite-difference time-domain algorithm to solve Maxwell's equations and Rethfeld's multiple rate equation model to consider the local excitation of a dense electron plasma. We validate our model by comparing the simulated transient reflectivity with experimental results and find excellent agreement.