中文摘要：

对掺铒光纤激光器的时域瞬态特性进行了理论与实验研究。理论模型从激光器的基本速率方程出发，通过求解增益光纤中的功率传输方程，得到激光器的时域输出结果。数值模拟了脉冲泵浦注入后激光器的瞬态特性，分析了激光器时域输出特性随泵浦功率及腔内损耗的变化规律。实验中采用上下沿功率均可调的方波泵浦掺铒光纤，通过可变光衰减器调解腔内损耗，观察激光器驰豫振荡特性，研究了激光建立的延迟时间与泵浦功率及腔损耗的关系。数值模拟与实验结果一致。

英文摘要：

The transient time-domain regime of the Er-doped fiber laser were studied experimentally and theoretically. According to the basic rate equation of laser, the time-domain regime of laser output were obtained by solving the power propagation equation in gain fibers. The variations of the time-domain regime of laser output were simulated with different pump powers and cavity losses. In this experiment, the Er-doped fiber laser was pumped by the square pulse whose high-level and low-level power could be adjusted. The cavity loss was modulated by the variable optical attenuator. The effect of pump power and cavity loss on the laser relaxation oscillation was studied in detail. The relationship among delay time, pump power and cavity loss was obtained. The experimental results are in good agreement with the theoretical results.