Chen Haidong, Wang Xinliang, Liu Xingyan, Chen Xun, Bai Peile, Pan Shuren, Hu Liang, Hu Jiabing, Wu Fenxiang, Zhang Zongxin, Liu Yanqi, Xu Yi, Leng Yuxin
Opt Express. 2023 Nov 20;31(24):40285-40292. doi: 10.1364/OE.506896.
Pre-pulses caused by the post-pulses in the optical parametric chirped-pulse amplifier were comprehensively studied for the first time, including the underlying mechanism for the delay-shift of pre-pulses, the intensity variation of pre-pulses affected by the initial delay of post-pulses and the pump energy, and also the nonlinear beat noise. The simulation and measurement confirmed that the high-order dispersion of the pulse stretcher was the main cause for the delay-shift of pre-pulses, which should be similar with the chirped-pulse amplifiers. The intensity of pre-pulses would decrease significantly as the initial delay of post-pulses increased, but would increase with the growth of pump energy. Moreover, the temporal position of the nonlinear beat noise in the experiment was successfully predicted by our simulation. This work could help us better understand the pre-pulses in OPCPA and provide helpful guidance for designing high-contrast laser systems.
首次对光参量啁啾脉冲放大器中后脉冲引起的预脉冲进行了全面研究，包括预脉冲延迟偏移的潜在机制、后脉冲初始延迟和泵浦能量对预脉冲强度变化的影响，以及非线性拍频噪声。模拟和测量证实，脉冲展宽器的高阶色散是预脉冲延迟偏移的主要原因，这与啁啾脉冲放大器的情况应该相似。随着后脉冲初始延迟的增加，预脉冲强度会显著降低，但会随着泵浦能量的增加而增加。此外，我们的模拟成功预测了实验中非线性拍频噪声的时间位置。这项工作有助于我们更好地理解光参量啁啾脉冲放大器中的预脉冲，并为设计高对比度激光系统提供有益的指导。
