用于高能啁啾脉冲压缩的光子晶体光栅的设计

 为了克服目前高能短脉冲装置压缩光栅的损伤阈值无法满足要求的问题，针对星光Ⅲ装置皮秒激光束的压缩器，设计了由熔石英材料构成的、具有较高损伤阈值的光子晶体光栅，该光栅由2维光子晶体和表面光栅结构两部分组成，具有高反射效率和强角色散的能力。计算结果显示:经过优化设计的光子晶体光栅在波长1 053 nm，57°～77°的入射范围内，-1级衍射效率超过了92%，而当入射角为71°时，在1 040～1 090 nm光谱范围内，-1级衍射效率超过92%，性能满足使用要求。

Design of photonic-crystal pulse-compression grating for high-energy chirped laser

The low threshold of compression gratings determines the maximum output energy of high-energy PW laser systems. For the compressor in the Xingguang-Ⅲ facility which is under development, this paper designed a 2-D photonic-crystal grating of fused silica which utilizes photonic crystal technology and the grating’s micro-structure. The results show that the diffraction efficiency of the minus first order of the grating exceeds 92% for incident angle from 57° to 77° when the incident wavelength is 1 053 nm, and for wavelength from 1 040 nm to 1 090 nm when the incident angle is 71°. The grating meets the requirements of wide spectral range (50 nm) and wide range of angle of incidence (18°).