振幅和相位涨落对锁模脉冲列特性的影响

Influence of amplitude and phase fluctuations on the characteristics of a mode-locked laser pulse train

用傅里叶变换的方法分析了锁模激光器中模式间的相位和振幅涨落对锁模脉冲列特性的影响。将锁模激光器中各模式的相位和振幅涨落作傅里叶展开,再通过增益谱抽样的傅里叶变化得到其时域行为。分析结果表明振幅系统涨落及随机涨落均不引起脉宽的明显变化,只引起脉冲间背景的加大,但相位涨落随机会使脉冲列强度产生波动。所用物理图像简明,结果对获得稳定的锁模脉冲列的实验研究有参考意义。

The Fourier transform method has been used to analyze the influence of modal amplitude and phase fluctuations in a mode-locked laser on performance of its output pulse. The results show that the pulse shape and the bandwidth remain essentially constant when the modes have amplitude and phase fluctuations, but appear superimposed on a fluctuations background. The phase variations will cause the fluctuation of peak. The physical picture in this paper is concise and is helpful to get stable modelocked laser output in experiments.