Effect of Dual-Pulse Temporal Shaping on Ultraviolet Nanosecond Laser Damage of Fused Silica Surface in High Fluence Regime

We present the effect of dual-pulse temporal shaping on ultraviolet nanosecond laser damage characteristics a fused silica exit surface in high fluence regime. The pre- and post-pulse have opposite effects behavior at pulse delay 20 ns. pre-pulse irradiation significantly increases main-pulse threshold, making it much higher than that single-pulse while has little threshold. For near-threshold sites, reduces average size depth, them smaller those single-pulse, drastically larger single-pulse. site is monotonously increased from 43.6 µm to 127.9 with increasing energy. shape factor 0.61, threshold main nearly stabilizes after 10 underlying mechanism temporal-shaping discussed based applied precursor modification absorption enhancement, which could provide insights for studying optics.