用SPIDER法还原飞秒脉冲振幅和相位误差

Error of spectral intensity and phase of femtosecond laser pulse using SPIDER technique

基于光谱位相相干直接电场重构法(SPIDER)测量飞秒激光脉冲的基本原理和重构飞秒脉冲的算法,数值模拟了SPIDER技术重构飞秒脉冲的过程,分析了时间延迟τ、光谱剪切量Ω的选取原则.以宽度约为50 fs的高斯型线性啁啾脉冲为例,取不同的时间延迟τ、光谱剪切量Ω重构了飞秒脉冲,得到:重构出的飞秒脉冲强度和位相最接近时,时间延迟τ约为2 260 fs,相对光谱剪切量Ω/Δω约为10%.

Based on the spectral phase interferometry of direct electric-field reconstruction （SPIDER）, the spectral phase and intensity of femtosecond laser pulse is reconstructed with numerical simulations. Two crucial parameters, the time delay r between the tested pulse replicas, and the frequency shear Ω are analyzed on how to choose their values. When the Gauss linearly chirped pulse＇s full width at the half maximum （FWHM） is about 50 fs, the phase is reconstructed with different time delay and different relative shearΩ/△ω. The optimum phase curve and intensity is about at τ=2 260 fs and relative shear at Ω/△ω=10% respectively.