【摘要】 惯性约束核聚变快点火实验,要求拍瓦终端输出再压缩的高信噪比超短激光脉冲。在拍瓦前端光参变啁啾脉冲放大(OPCPA)阶段,抽运激光脉冲中由放大的自发辐射(ASE)噪声调制导致的电场强度振幅和相位的随机扰动,将会被传递到信号光的光谱上,使再压缩后主激光脉冲前后出现底座,降低了信号光的信噪比。数值模拟了抽运激光脉冲中ASE噪声对信噪比以及对时间底座的宽度的影响,并探讨了有利于提高超短激光脉冲信噪比的途径。更多还原

【Abstract】 The fast ignitor scheme in inertial confined fusion requires ultrashort laser pulse with high signal-to-noise ratio (SNR). The amplified spontaneous emission (ASE) noise modulations in pump pulse are transferred onto the signal spectrum and these modulations of signal spectrum generate the time-pedestal before and after this main pulse, which degrades the signal-to-noise ratio. The restrictions of the SNR by the random ASE noise and the duration of its pedestal are numerically modeled. A number of ways that can reduce the noise level and increase the signal-to-noise ratio are discussed.更多还原