反射式棱栅对展宽器用于啁啾脉冲放大激光的研究

在啁啾脉冲放大(CPA)系统中, 脉冲的展宽是实现安全有效放大的重要保证. 本文介绍了一种新型的由色散棱镜与光栅组合而成的反射式棱栅对展宽器. 并利用光线追迹法对色散进行了数值模拟, 测量实验结果验证了理论计算的正确性. 在此基础上, 分析了以棱栅对为展宽器和ZF7玻璃材料为压缩器的下啁啾(down-chirped)脉冲放大系统中的色散比较传统的上啁啾脉冲放大系统, 结果表明棱栅对可以同时提供负的二阶色散和三阶色散, 这样能更好地补偿放大器中材料的高阶色散, 从而获得近傅里叶变换极限的压缩脉冲. 此外以块材料作为压缩器不仅提高了传输效率, 而且简化了实验装置, 增强了系统的稳定性. 这样的展宽压缩组合在高重复频率的飞秒啁啾脉冲放大系统中具有明显优势.关键词：反射式棱栅对啁啾脉冲放大色散飞秒脉冲

A reflective grism pair stretcher for chirped pulse amplification

A new reflective grism, which combines together the grating and prism, is introduced in this paper. The numerical simulation, based on the ray tracing, shows that the grism pair can introduce minus GVD and GDD; therefore it can well compensate for the material dispersions in the chirped pulse amplifier (CPA). Compared to the conventional CPA with up-chirp, the new scheme with down-chirp can support a near Fourier Transform-limited compressed pulse due to much better compensation for high-order dispersion of materials in amplifier, in which the grism acts as the stretcher and the ZF7 bulk material as the compressor. In addition, the improved transmission efficiency and simplified configuration makes it a promising way to amplify femtosecond laser pulses to sub-mJ at a high repetition rate.
Keywords：reflective grism pairchirped pulse amplificationdispersionfemtosecond pulse