Pulsed laser-induced damage threshold studies of thin aluminum films on quartz: Simultaneous monitoring of optical and acoustic signals.

Simultaneous measurements by two techniques for in situ laser-induced damage threshold (LIDT) detection, based on optical diffraction and acoustic measurements, were demonstrated. Pulsed Nd:YAG laser (532 nm) ablation of 25-nm-thick aluminum films on quartz was studied as a test case. The two probes gave consistent LIDT values, and were sensitive and simple to operate. For above-threshold ablation, the diffraction and acoustic signals were found to be strongly correlated, rendering them useful not just for threshold detection, but for studying ablation dynamics as well. [ABSTRACT FROM AUTHOR]