Spectroscopic investigation of laser-induced material modifications

Summary form only given.Understanding of the fundamental mechanisms associated with the energy deposition from a high power laser pulse into a transparent dielectric material is of critical importance for the development and employment of high power lasers. Basic research studies in this field have been kindled by the desire to produce optical materials with reduced susceptibilities to laser-induced catastrophic breakdown. Laser induced damage is accompanied with a characteristic emission indicative of plasma formation. The result of this process is that the material at the damage site is modified from its original composition and structure. In this work, we investigate photophysical processes associated with excessive light absorption of 355 nm, nanosecond laser pulses by optical materials. The experimental approaches utilized include time-resolved and steady state emission and Raman scattering spectroscopy. Experiments were performed on KH/sub 2/PO/sub 4/ crystals and fused silica.