Wang Hongyang, Qi Dongfeng, Yu Xiaohan, Zhang Yawen, Zhang Zifeng, Xu Tiefeng, Zhang Xiaowei, Dai Shixun, Shen Xiang, Song Baoan, Zhang Peiqing, Xu Yinsheng
Laboratory of Infrared Materials and Devices, The Research Institute of Advanced Technologies, Ningbo University, Ningbo 315211, China.
College of Mechanical and Electronic Engineering, Chaohu University, Hefei 230000, China.
Materials (Basel). 2018 Dec 26;12(1):72. doi: 10.3390/ma12010072.
Femtosecond laser pulse of 800 nm wavelength and 150 fs temporal width ablation of As₂S₃ chalcogenide glasses is investigated by pump-probing technology. At lower laser fluence (8.26 mJ/cm²), the surface temperature dropping to the melting point is fast (about 43 ps), which results in a clean hole on the surface. As the laser fluence increases, it takes a longer time for lattice temperature to cool to the melting point at high fluence (about 200 ps for 18.58 mJ/cm², about 400 ps for 30.98 mJ/cm²). The longer time of the surface heating temperature induces the melting pool in the center, and accelerates material diffusing and gathering surrounding the crater, resulting in the peripheral rim structure and droplet-like structure around the rim. In addition, the fabricated long periodic As₂S₃ glasses diffraction gratings can preserve with high diffraction efficiency by laser direct writing technology.
采用泵浦探测技术研究了波长为800 nm、脉宽为150 fs的飞秒激光脉冲对As₂S₃硫系玻璃的烧蚀情况。在较低的激光能量密度（8.26 mJ/cm²）下，表面温度降至熔点的速度很快（约43 ps），这使得表面形成一个干净的孔洞。随着激光能量密度的增加，在高能量密度下晶格温度冷却至熔点所需的时间更长（对于18.58 mJ/cm²约为200 ps，对于30.98 mJ/cm²约为400 ps）。表面加热温度持续时间较长会在中心形成熔池，并加速材料在火山口周围的扩散和聚集，从而形成周边边缘结构以及边缘周围的液滴状结构。此外，通过激光直写技术制备的长周期As₂S₃玻璃衍射光栅能够以高衍射效率保存下来。
