In this study, ZnS/YbF₃-10.6 µm antireflection (AR) coatings were fabricated on CVD single-crystal diamond and ZnSe substrates. The spectral characteristics of the coatings and their performance under continuous wave laser radiation at 10.6 µm were systematically investigated. The fabricated AR coatings exhibited excellent spectral properties in the target wavelength range. Both theoretical calculations and experimental results indicated that, at the same power density, the 10.6 µm AR coatings on diamond substrates exhibited a lower temperature rise compared to those deposited on ZnSe substrates. Due to its high thermal conductivity, the diamond substrate is expected to exhibit reduced thermally induced surface distortion. The laser-induced damage threshold (LIDT) test results indicate that the AR coating deposited on the ZnSe substrate exhibits a damage threshold of 11,890 W/cm², whereas the AR coating on the diamond substrate achieves a threshold of 15,287 W/cm², representing a 28.5% improvement over the ZnSe substrate. Additionally, graphite formation occurs on the diamond substrate under high power density. These findings provide both theoretical and experimental support for the potential application of diamond materials in high-power laser systems.

Mo/Al multilayers have the potential to be used as reflective mirrors in telescopes for cosmic and solar observation in a large spectral range of extreme ultraviolet radiation. Two types of Mo/Al multilayers were deposited by a magnetron sputtering system for comparison: one used pure Al and one used Al doped with 1.5wt. % Si. The structural performance of these two multilayers were characterized by a X-ray diffractometer, atomic force microscope, and optical profilometer. The angular dependence of the reflectivity was measured using a laboratory-based reflectometer at 58.4 nm. Grazing incidence X-ray reflectivity analysis revealed that the Mo/Al (1.5wt. % Si) multilayers possess a significantly improved interfacial structure compared with Mo/Al (pure). Surface morphology observations of the samples indicated that the incorporation of Si smoothes the surface and reduces the surface roughness. X-ray diffraction results suggest that the Si slightly reduces the average grain size of Al and increases the average grain size of Mo, but their crystallinity is improved. Based on the improvement of structural performance, a peak reflectivity of 29.4% at 58.4 nm is achieved for Mo/Al (1.5%Si) multilayers, whereas it is only 17.4% for Mo/Al (pure).