Effect of Dual-Pulse Temporal Shaping on Ultraviolet Nanosecond Laser Damage of Fused Silica Surface in High Fluence Regime
Wenfeng Liu,
Mingying Sun,
Yajing Guo,
Yiqun Shi,
Yingming Xu,
Zhaoyang Jiao,
Zijian Cui,
Jianqiang Zhu
Affiliations
Wenfeng Liu
National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Mingying Sun
National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Yajing Guo
National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Yiqun Shi
National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Yingming Xu
National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Zhaoyang Jiao
National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Zijian Cui
National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Jianqiang Zhu
National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
We present the effect of dual-pulse temporal shaping on the ultraviolet nanosecond laser damage characteristics of a fused silica exit surface in a high fluence regime. The pre- and post-pulse have the opposite effects on the damage behavior at a pulse delay of 20 ns. The pre-pulse irradiation significantly increases the main-pulse threshold, making it much higher than that of the single-pulse threshold, while the post-pulse has little effect on the main-pulse threshold. For near-threshold damage sites, the pre-pulse reduces the average damage size and depth, making them smaller than those of the single-pulse, while the post-pulse drastically increases the average size and depth, making them much larger than those of the single-pulse. The average size of the damage site is monotonously increased from 43.6 µm to 127.9 µm with increasing post-pulse energy. For the pre-pulse with a shape factor of 0.61, the damage threshold of the main pulse increases with increasing delay and nearly stabilizes after 10 ns. The underlying mechanism of the temporal-shaping effect on laser damage is discussed based on the applied precursor modification to absorption enhancement, which could provide insights for studying ultraviolet laser damage of fused silica optics.
