Chapter Seven - Physics and Chemistry of Laser-Liquid-Solid Interactions

Abstract

This chapter describes the physical and chemical interactions between laser, liquids, and solids. It begins with a description of nomenclature of laser beams and their propagation. Based on this, it describes the properties of Gaussian beams. It then discusses reflectivity and transmittance of an interface between two media, reflectivity of two parallel interfaces, and reflectivity of liquid–plasma interface. It also explains the propagation of Gaussian beams. Following this, it deals with the phase change phenomenon, discussing the process of vaporization from free liquid surfaces, nucleation of vapor bubbles, and bubble dynamics. The optical breakdown of liquid and plasma is also discussed. It then considers photoionization of a dielectric liquid, cascade ionization, thermal ionization, diffusion loss of electrons from the plasma, recombination loss, thermal conductivity of the plasma, rate equation for free electrons, internal energy density of electrons and particles in plasma, and energy balance equation for electrons. Furthermore, it deals with shock waves in liquids and solids. It also describes laser-induced reactions of carbon with organic solvents and water. Finally, it sheds light on the behavior of oxides in high temperature water and water vapor.