应用级联倍频方法提高倍频系统输出稳定性研究

提出应用级联倍频方法提高倍频系统输出稳定性,并就该方法的有效性进行了理论分析和模拟计算.分析和计算结果不但证明级联倍频方法能实现倍频系统稳定输出,而且还表明可以通过仔细调节第一块倍频晶体中波矢方向 k 与光轴间夹角、两块倍频晶体间的间隔,能调节改变实现倍频系统最稳输出时所需第二块晶体的理论计算长度,使之与第二块倍频晶体的实际加工长度一致,最终实现系统稳定倍频输出.级联倍频方法在实现高输出稳定性的同时能实现高的倍频转换效率,对应用于光参量啁啾脉冲放大系统的高稳定抽运源系统的设计建造具有重要参考意义. 关键词： 级联倍频 稳定倍频输出 光参量啁啾脉冲放大

Stabilizing second harmonic generation output using cascaded crystals

Theoretical study and numerical simulation were carried out on the newly proposed way of cascaded second harmonic generation (SHG) to get stable SHG output. The results certify that by way of using cascaded SHG one can obtain stable SHG output. Our results also show that by tuning the angle between k and the optical axis and the distance between the two SHG crystals, the length of the second SHG crystal for most stable SHG can also be tuned. When the length for most stable SHG is tuned to the real length of the second SHG crystal, stable SHG output was be obtained. Both stable SHG output and high SHG conversion efficiency can be got using this new way, and this will help a lot to design the pumping system for the optical pulse chirped amplifying system.