基于双密度棱栅的新型超短脉冲色散补偿装置

Double-Line-Density Grisms for Dispersion Compensation of Ultra-Short Laser Pulses

针对光参量啁啾脉冲放大系统中的色散特性,提出了一种基于双密度棱栅的新型超短脉冲色散补偿装置。该色散补偿装置包括一对互相平行的光栅和一对斜边平行放置的同等大小的等腰直角棱镜,第二个光栅的线密度是第一个的两倍。建立光线追迹模型,通过数值计算,讨论了装置各结构参数对装置色散补偿量的影响。结果表明,该装置可以在补偿系统剩余线性啁啾(二阶色散)量的基础上,独立补偿三阶色散,且补偿量可在较大正负范围内变化,适用于飞秒量级超短啁啾脉冲系统的色散控制。

A new device for dispersion compensation of ultra-short laser pulses is developed. This setup is made up of a pair of double-line-density grisms. Each grism consists of a prism and a grating separated from each other. It is featured that the density of the second grating doubles the first one＇s. The numerical results of ray tracing show that this setup can compensate third-order dispersion independently without any spatial distortion, and the compensation sphere covers a wide scale from negative to positive. It provides a certain reference for dispersion compensation of femtosecond pulses in chirped pulse amplification systems.