Laser-induced bulk damage in SiO2 at 1.064, 0.532, and 0.355 μm

Abstract

Single- and multiple-pulse laser-induced bulk damage of fused and crystalline SiO2 has been investigated. We studied the dependence of the intensity required to produce macroscopic damage upon wavelength, focal spot size, pulse duration, and pulse repetition frequency. It is found that the material must undergo some undetected microscopic change prior to macroscopic damage which increases the probability of damage with increasing number of pulses. The multiple pulse damage depends strongly on spot size, occurring in far fewer pulses at larger spot sizes than at small ones, and displays a significant dependence on pulse length and repetition frequency. Possible mechanisms are discussed.