Experimental investigation of phase explosion by irradiating thin aluminum targets with high power pulsed laser beam

In this paper phase explosion in aluminum targets induced by Nd:YAG pulsed laser beam is studied. The phase explosion occurs in ablation process when the Nd:YAG laser beam (single pulse) is focused on the surface of target in ambient air. The phase explosion was investigated by monitoring the transmission of a cw laser probe beam through the ablating region. Two different aluminum targets were used in this study; a thin film aluminum on a quartz substrate, and a thick aluminum foil. The results show that the probe beam transmission through the ablated region is enhanced significantly when the laser fluence is enough for the phase explosion to be occurred.