Laser breakdown in water induced by λ = 532 nm nanosecond pulses: Analytical calculation of the number density of free electrons

Abstract

© 2020 The Physical Society of Japan. In this paper a model for laser induced breakdown in water is presented, that includes the net gain and losses of the free electron density. In this regard we adopted a simple theoretical formulation relying on the analytical solution of a rate equation that describes the growth of the electron density due to the joined effect of multiphoton and cascade ionization processes. Here, the rate also includes the effect of electron loss due to electron diffusion and electron-ion recombination processes. The analysis considered a Nd:YAG laser radiation at a wavelength of 532nm with 6 ns pulse duration full-width half-maximum (FWHM).