Damage Performance of Multilayer Films under Simultaneous Exposure to Multi-Wavelength Pulses

Laser damage performance of multilayer films with combined irradiation of 1ω and 2ω is studied to probe the damage mechanisms during wavelength division. The laser induced damage thresholds (LIDTs) of the samples are obtained and tested with only 2ω with various energy densities of 1ω. Different 1ω polarization directions combined with the 2ω case are also investigated. The result suggests that 1ω can raise the damage probability of multilayer mirrors when two light wavelengths are present simultaneously; the increasing number of sensitive defects for 2ω can be related to the decline of the LIDTs of the multilayer mirrors.