通过研究光参量啁啾脉冲放大(OPCPA)过程增益谱随抽运光中心波长的变化,提出了啁啾匹配OPCPA方法。以KDP晶体为例,研究了啁啾匹配与啁啾非匹配两种OPCPA方式的信号光时域和频域特性,以及放大前后脉冲时间波形和频谱形状的变化等。结果表明,非啁啾匹配时,将出现明显的增益窄化现象;而采用啁啾匹配的方法可以大大增加增益谱宽,从而不会出现增益窄化现象。

Chirp matched optical parametric chirped pulse amplification method (OPCPA) has been proposed by studying the variation of OPCPA gain spectrum with the pump optical center wavelength. Taking nonlinear KDP crystal as an example,the temporal and spectral gain characteristics of the chirp matched and mismatched OPCPA methods have been studied. Furthermore,the changes of the temporal and the spectral profiles before and after the OPCPA have been analyzed in details. The results show that the gain narrowing phenomenon becomes significant for the chirp mismatched case. However,the gain spectrum width is greatly increased by using chirp matched method,eliminating the gain narrowing phenomenon.