On the possible effect of pedestal pulse on material removal by ultrahigh intensity laser pulses

Abstract

The results of the interaction of 200 fs and 4 ns laser pulses produced by a Ti : Sapphire commercial laser system with various materials are reported. The drilling rates were measured as a function of laser pulse energy and material thickness. Saturation of the material removal rate was observed for high laser pulse energy. The dependence of the material removal rate on the sample thickness was measured. The results of numerical simulation of laser drilling with femtosecond and nanosecond laser pulses using a theoretical model which includes phase transition at the critical temperature are reported. The computed drilling rates are in agreement with the data of measurements. The effect of a suspected nanosecond pedestal pulse containing approximately 30% of total pulse energy on the rate of drilling with femtosecond laser pulses is numerically simulated and the computed results are discussed.