基于种子光特性优化的光纤放大器理论分析

种子光特性直接影响放大脉冲的特性,为获得高质量放大脉冲输出,文章对基于SESAM被动锁模光纤放大器中种子光的特性进行优化模拟。理论分析了锁模光纤激光器的单模光纤长度、增益光纤长度、滤波器带宽以及输出耦合比的变化对种子光特性的影响,以及种子光携带的啁啾对放大脉冲的影响。综合色散和非线性效应等对种子光的影响,得到各项参数的最优值,并进行两级放大模拟,最终获得脉冲宽度为1353 ps、光谱宽度为115nm、平均功率为61W的高质量放大脉冲。

Theoretical analysis of fiber amplifier based on optimization of seed optical characteristics

The characteristics of seed light directly affect the characteristics of amplifying pulse. In order to obtain high quality amplifying pulse output,the seed light characteristics of passive mode locked fiber amplifier based on SESAM are optimized and simulated in this paper. The influences of the length of the single mode fiber,the length of the gain fiber,the filter bandwidth and the output coupling ratio of the mode locked fiber laser on the optical properties of the seed and the effect of chirp carried by the seed light on the amplification pulse are analyzed theoretically. The optimal values of various parameters are obtained by integrating the effects of dispersion and nonlinear effects on the seed light,and the two stage amplification simulation is carried out. Finally,a high quality amplification pulse with a pulse width of 12.79 ps,a spectral width of 13 nm and an average power of 6.1 W is achieved.