Maximizing the energy-loading performance of gratings is a universal theme in high-energy pulse compression. However, sporadic grating designs strongly restrict the development of high-power laser engineering. This study proposes an all- and mixed-dielectric grating design paradigm for Nd:glass-based pulse compressors. The solution regions are classified according to the line density. High diffraction efficiency solutions are described in more detail based on the dispersion amount and incident angle. Moreover, an energy scaling factor of 7.09 times larger than that of the National Ignition Facility’s Advanced Radiographic Capability (NIF-ARC) is obtained by taking advantage of the low electric field intensity at transverse magnetic polarization and a small incident angle. These results make a pioneering contribution to facilitate future 20–50-petawatt-class ultrafast laser systems.

脉冲压缩光栅是实现高能量激光的核心光学元器件，其制造过程中产生的表面污染物和微结构缺陷成为限制高功率激光系统发展的技术瓶颈，为了提升光栅的激光诱导损伤阈值，提出利用磁性复合流体进行脉冲压缩光栅（PCG）后处理抛光研究。对抛光前后光栅样品的微观结构，表面形貌、表面粗糙度、衍射效率和激光诱导损伤阈值等参数进行测量，进行抛光前后光栅表面质量和光栅性能的评估。研究发现，磁性复合流体抛光能够在不破坏实际光栅结构的前提下抑制加工过程产生的毛刺，微结构缺陷等；经3 min抛光后，光栅顶部表面粗糙度从21.36 nm下降到3.73 nm；激光诱导损伤阈值从2.8 J/cm²提高到3.8 J/cm²，抗激光损伤性能提升35.7%，且不影响衍射效率。实验结果表明：磁性复合流体抛光是一种可以提高光栅元件表面质量，提升光栅元件光学性能的有效方法。