Department of Engineering Science, National Cheng Kung University, Tainan 701, Taiwan.
Opt Lett. 2010 Jul 15;35(14):2490-2. doi: 10.1364/OL.35.002490.
We have conducted experimental investigations for the micromachining of dielectrics (fused silica) using an integrated femtosecond (fs) and nanosecond (ns) dual-beam laser system at different time delays between the fs and ns pulses. We found that the maximum ablation enhancement occurs when the fs pulse is shot near the peak of the ns pulse envelope. Enhancements up to 13.4 times in ablation depth and 50.7 times in the amount of material removal were obtained, as compared to fs laser ablation alone. The fs pulse increases the free electron density and changes the optical properties of fused silica to have metallic characteristics, which increases the absorption of the ns laser energy. This study provides an opportunity for efficient micromachining of dielectrics.
我们使用集成飞秒（fs）和纳秒（ns）双光束激光系统在 fs 脉冲和 ns 脉冲之间不同的时间延迟进行了用于加工电介质（熔融石英）的实验研究。我们发现，当 fs 脉冲在 ns 脉冲包络的峰值附近发射时，会发生最大的烧蚀增强。与单独的 fs 激光烧蚀相比，烧蚀深度增加了 13.4 倍，去除的材料量增加了 50.7 倍。fs 脉冲会增加自由电子密度，并改变熔融石英的光学性质，使其具有金属特性，从而增加了 ns 激光能量的吸收。这项研究为高效加工电介质提供了机会。
