Phase Explosion in Silicon and Titanium Targets Irradiated by Third Harmonic Nd-YAG Pulsed Laser

Abstract

In this work, the combined diagnostic measurements of ablated material by scanning electron microscopy of the craters and ion time of flight analysis have been employed to study the interaction of third harmonic Nd-Yag laser with silicon and titanium target. Evidence for the transition from normal vaporization to phase explosion has been obtained, showing an abrupt increase in the mass ablation rate beyond a laser intensity threshold and round-shaped micrometer-sized cavities found on the irradiated areas. Ion time of flight analysis is used to estimate the surface temperature under near threshold ablation conditions.