非单色光抽运的光参量啁啾脉冲放大的带宽及增益特性研究

采用傅里叶变换的方法将脉冲光分解成不同的频率成分，建立了非单色光抽运的光参量放大耦合方程组的数值求解模型.研究了非单色抽运光对光参量啁啾脉冲放大的小信号增益、大信号增益以及增益带宽的影响.非单色抽运光降低参量放大的增益水平，但同时可提高增益带宽，且抽运光谱宽越宽，对增益带宽的提高作用越大.还进一步从相位失配和参量带宽的角度分析了非单色抽运光使参量放大的增益降低、带宽增大的原因. 关键词： 光参量啁啾脉冲放大 非单色光 增益带宽 飞秒激光

Bandwidth and gain of optical parametric chirped pulse amplification pumped by non-monochromatic light

Laser pulse was decomposed into components of different frequencies using Fourier transform, and the numerical calculation model was built up for coupled equations of optical parametric amplification pumped by non-monochromatic light. Effects of non-monochromatic light on small signal gain, large signal gain and gain bandwidth of optical parametric amplification were investigated. Though non-monochromatic pump light decreases the gain of optical parametric process, it can improve the gain bandwidth. The larger the bandwidth of the pump light, the wider the gain bandwidth. Reasons for parametric gain decrease and gain bandwidth improvement were analyzed with respect to the phase mismatch and the parametric bandwidth.