Comparisons and analyses of the properties of laser-induced damage to SiO₂ and ZnS

Abstract

To compare the optical damage resistance ability of SiO₂ and ZnS, the processes of electrons reproduction of the two materials have been studied. The relationship of multiphoton ionization rate, avalanche ionization rate and the multiphoton parameter < x + 1 > with the intensity of the incident laser is calculated. The damage thresholds induced by the laser with different pulse widths are calculated too. In addition, the respectable role of the recombination and diffusion for an electron in the electronic proliferation processes is examined. Calculation results show that SiO₂ has a higher damage threshold while τ < 1 ns, and ZnS has a higher damage threshold while τ > 1 ns.

Keywords:

• damage threshold
• infrared material
• pulse width