Measurement of optical losses and damage resistance of ZnSNa"3AlF"6 and TiO"2SiO"2 laser mirrors depending on coating design - Welsch, E.; Walther, H.G.; Schafer, D.; Wolf, R. (Elsevier)
Quarterwave ZnSNa"3AlF"6 and TiO"2SiO"2 multilayer stacks were prepared to investigate correlations between optical absorption, scattering and laser damage resistance at λ = 488 nm, 515 nm and 530 nm respectively. The coating design was varied to assist the investigation.The ratio of interface to volume contributions to the optical losses was shown to depend on the coating material and deposition process used. The highest damage resistance was found in multilayer systems which consist of an alternating set-up of a λ/4 high refracting and a 3λ/4 low refracting component. Thus, the correlation between absorption and damage may not be established in each case, as the damage becomes design dependent. To explain this result, it is necessary to take into account the heat flow within the stacks investigated during laser irradiation as well as an additionally acting laser-induced thermal stress giving rise to a different damage resistance in the multilayer stacks.
http://linkinghub.elsevier.com/retrieve/pii/0040-6090(87)90258-6
Keywords: U