【摘要】 参量荧光是基于光参量啁啾脉冲放大(OPCPA)技术的光参量放大器的本征量子噪声。它不具备与主激光相同的时域啁啾特性,在压缩器中形成不可压缩的脉冲底座,降低了激光脉冲的信噪比。在小信号增益情况下,基于解析公式给出了不同抽运波形、不同增益、不同系统带宽和啁啾率情况下参量荧光脉宽的演化规律。结果表明:单级放大器输出荧光脉宽正比于抽运光脉宽;荧光脉宽随着增益的增大而变小;增益一定的情况下,荧光脉宽随着超高斯波形阶数的增大而变大。对OPCPA系统而言,展宽-压缩系统对荧光存在色散展宽的作用,其最终输出荧光脉宽与系统带宽、啁啾率紧密相关。基于拍瓦OPCPA(PW-OPCPA)实验平台进行了相关的验证实验,实验结果与理论具有良好的一致性。更多还原

【Abstract】 Parametric fluorescence is the intrinsic quantum noise of optical parametric amplifiers based on optical parametric chirped pulse amplification(OPCPA)technology.It does not have the same temporal chirp characteristics with the main laser,forms an incompressible pulse base in the compressor,and reduces the signal-to-noise ratio of the laser pulse.In the case of small signal gain,the evolution laws of parametric fluorescence pulse width with different pump profiles,gains,system bandwidths and chirp rates are given based on the analytical formula.Results show that the single stage amplifier output fluorescence pulse width is proportional to the pump pulse width,and it decreases with the gain increasing.With a constant gain,the fluorescence pulse width becomes larger with the increase of the super Gaussian wave order.For OPCPA system,the stretch-compression system has the effect of dispersion broadening,so the final output fluorescence pulse width is closely related to the system bandwidth and chirp rate.Based on petawatt OPCPA(PW-OPCPA)experimental platform,the relevant verification experiments are carried out,and the experimental results are in good agreement with the theoretical results.更多还原