对掺Yb3+双包层光纤激光器的输入输出特性进行了实验研究。实验中发现当泵浦功率略超过阈值后,光纤输出功率开始变得不稳定,在一定范围内反复上下波动,并有明显的周期性,即出现所谓“自脉动”行为。利用可饱和吸收体模型对作用的具体过程给出了一种新的解释。 The input and output characteristics of doped Yb3 + double clad fiber laser were experimentally studied. Experiments show that when the pump power slightly exceeds the threshold, the optical fiber output power begins to become unstable, fluctuating repeatedly within a certain range, and there is a significant periodicity, that is, so-called “self-pulsation” behavior. A new explanation of the specific process of action is given by using saturable absorber model.