Damage induced by inclusions in coatings under repetition frequency pulse laser

By the model of damage induced by inclusions in dielectric thin-films, with the experiment done by S.Papernov et al who deposited HfO2 thin-films containing gold nanoparticles on a cleaved fused-silica by e-beam evaporation, the absorption cross-section of gold was obtained. Furthermore, the laser-induced damage thresholds of HfO2 film induced by Au inclusions with varies radius and varies repetition frequency were calculated. The results indicate that the minimum energy density causing damage decreases first, then increases, finally decreases again with the increasing impurity radius. The relationship between the damage threshold and the damage shot number both change near-linearly with the repetition rate increase, while the former is descending, and the latter is ascending.