Nanosecond single- and multiple-pulse laser damage studies on HfOffSiO2 high-reflection （HR） coatings are performed at 532 nm. For single-pulse irradiation, the damage is attributed to the defects and the electric i...Nanosecond single- and multiple-pulse laser damage studies on HfOffSiO2 high-reflection （HR） coatings are performed at 532 nm. For single-pulse irradiation, the damage is attributed to the defects and the electric intensity distribution in the multilayer thin films. When the defect density in the irradiated area is high, delami- nation is observed. Other than the 1064 nm laser damage, the plasma scalding of the 532 nm laser damage is not pits-centered for normal incidence, and the size of the plasma scalding has no relation to the defect density and position, but increases with the laser fluence. For multiple-pulse irradiations, some damage sites show deeper precursors than those from the single-shot irradiation due to the accumulation effects. The cumulative laser- induced damages behave as pits without the presence of plasma scalding, which is unaffected by the laser fluence and shot numbers. The damage morphologies and depth information both confirm the fatigue effect of a HfO2/SiO2 HR coating under 532 nm laser irradiation.展开更多
The experiment setup of a reflecting combination device, which has more advantages than a transmitting combination device, is designed in this study. To achieve angular spectrum selectivity, only one type of reflectiv...The experiment setup of a reflecting combination device, which has more advantages than a transmitting combination device, is designed in this study. To achieve angular spectrum selectivity, only one type of reflective component is needed,so difficulties of design and preparation are reduced. A dielectric multilayer film is applied to the reflective component, and the long wave-pass coating stacks of the structure are designed. To achieve high stopband transmittance and reduce electric field intensity at a wavelength of 1053 nm, an objective function is proposed for designing an optimized coating. The final optimized coating has good spectral characteristics and a high laser-induced damage threshold. A dielectric multilayer film with high reflectance plays an important role in preparing and applying a dielectric multilayer film reflecting cutoff filter-combination device.展开更多
基金supported by the National Natural Science Foundation of China under Grant Nos.11104293and 61308021
文摘Nanosecond single- and multiple-pulse laser damage studies on HfOffSiO2 high-reflection （HR） coatings are performed at 532 nm. For single-pulse irradiation, the damage is attributed to the defects and the electric intensity distribution in the multilayer thin films. When the defect density in the irradiated area is high, delami- nation is observed. Other than the 1064 nm laser damage, the plasma scalding of the 532 nm laser damage is not pits-centered for normal incidence, and the size of the plasma scalding has no relation to the defect density and position, but increases with the laser fluence. For multiple-pulse irradiations, some damage sites show deeper precursors than those from the single-shot irradiation due to the accumulation effects. The cumulative laser- induced damages behave as pits without the presence of plasma scalding, which is unaffected by the laser fluence and shot numbers. The damage morphologies and depth information both confirm the fatigue effect of a HfO2/SiO2 HR coating under 532 nm laser irradiation.
文摘The experiment setup of a reflecting combination device, which has more advantages than a transmitting combination device, is designed in this study. To achieve angular spectrum selectivity, only one type of reflective component is needed,so difficulties of design and preparation are reduced. A dielectric multilayer film is applied to the reflective component, and the long wave-pass coating stacks of the structure are designed. To achieve high stopband transmittance and reduce electric field intensity at a wavelength of 1053 nm, an objective function is proposed for designing an optimized coating. The final optimized coating has good spectral characteristics and a high laser-induced damage threshold. A dielectric multilayer film with high reflectance plays an important role in preparing and applying a dielectric multilayer film reflecting cutoff filter-combination device.
