Multilayer dielectric gratings(MLDGs)are crucial for pulse compression in picosecond-petawatt laser systems.Bulged nodular defects,embedded in coating stacks during multilayer deposition,influence the lithographic pro...Multilayer dielectric gratings(MLDGs)are crucial for pulse compression in picosecond-petawatt laser systems.Bulged nodular defects,embedded in coating stacks during multilayer deposition,influence the lithographic process and performance of the final MLDG products.In this study,the integration of nanosecond laser conditioning(NLC)into different manufacturing stages of MLDGs was proposed for the first time on multilayer dielectric films(MLDFs)and final grating products to improve laser-induced damage performance.The results suggest that the remaining nodular ejection pits introduced by the two protocols exhibit a high nanosecond laser damage resistance,which remains stable when the irradiated laser fluence is more than twice the nanosecond-laser-induced damage threshold(nanosecond-LIDT)of the unconditioned MLDGs.Furthermore,the picosecond-LIDT of the nodular ej ection pit conditioned on the MLDFs was approximately 40%higher than that of the nodular defects,and the loss of the grating structure surrounding the nodular defects was avoided.Therefore,NLC is an effective strategy for improving the laser damage resistance of MLDGs.展开更多
Shock compression driven by nanosecond-laser techniques generates extreme pressure and temperature conditions in materials,enabling the study of high-pressure phase transitions and the behavior of materials in extreme...Shock compression driven by nanosecond-laser techniques generates extreme pressure and temperature conditions in materials,enabling the study of high-pressure phase transitions and the behavior of materials in extreme environments.These dynamic high-pressure states are relevant to a wide range of phenomena,including planetary formation,asteroid impacts,spacecraft shielding,and inertial confinement fusion.The integration of advanced X-ray diffraction experimental techniques,from laser-induced X-ray sources and X-ray free-electron lasers,and theoretical simulations has provided unprecedented insights into material behavior under extreme conditions.This perspective reviews recent advances in dynamic high-pressure research and the insights that they can provide,concentrating on dynamical phase transitions,metastable and transient states,the influence of crystal orientation,microstructural changes,and the kinetic mechanism of phase transitions across a variety of interdisciplinary fields.展开更多
基金supported by the National Key R&D Program of China(Grant No.2018YFE0115900)the Key Foreign Cooperation Projects of Bureau of the International Cooperation of Chinese Academy of Sciences(Grant No.181231KYSB20210001)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA25020314).
文摘Multilayer dielectric gratings(MLDGs)are crucial for pulse compression in picosecond-petawatt laser systems.Bulged nodular defects,embedded in coating stacks during multilayer deposition,influence the lithographic process and performance of the final MLDG products.In this study,the integration of nanosecond laser conditioning(NLC)into different manufacturing stages of MLDGs was proposed for the first time on multilayer dielectric films(MLDFs)and final grating products to improve laser-induced damage performance.The results suggest that the remaining nodular ejection pits introduced by the two protocols exhibit a high nanosecond laser damage resistance,which remains stable when the irradiated laser fluence is more than twice the nanosecond-laser-induced damage threshold(nanosecond-LIDT)of the unconditioned MLDGs.Furthermore,the picosecond-LIDT of the nodular ej ection pit conditioned on the MLDFs was approximately 40%higher than that of the nodular defects,and the loss of the grating structure surrounding the nodular defects was avoided.Therefore,NLC is an effective strategy for improving the laser damage resistance of MLDGs.
基金supported by the National Natural Science Foundation of China under Grant Nos.12534013,12035002,12047561,and 12104507as well as the Science and Technology Innovation Program of Hunan Province under Grant No.2021RC4026+1 种基金T.Sekine gratefully acknowledges financial support from the Shanghai Key Laboratory of Material Frontiers Research in Extreme Environments,China(Grant No.22dz2260800)from the Shanghai Science and Technology Committee,China(Grant No.22JC1410300).
文摘Shock compression driven by nanosecond-laser techniques generates extreme pressure and temperature conditions in materials,enabling the study of high-pressure phase transitions and the behavior of materials in extreme environments.These dynamic high-pressure states are relevant to a wide range of phenomena,including planetary formation,asteroid impacts,spacecraft shielding,and inertial confinement fusion.The integration of advanced X-ray diffraction experimental techniques,from laser-induced X-ray sources and X-ray free-electron lasers,and theoretical simulations has provided unprecedented insights into material behavior under extreme conditions.This perspective reviews recent advances in dynamic high-pressure research and the insights that they can provide,concentrating on dynamical phase transitions,metastable and transient states,the influence of crystal orientation,microstructural changes,and the kinetic mechanism of phase transitions across a variety of interdisciplinary fields.
