Su Qingchao, Wang Tianshu, Zhang Jing, Ma Wanzhuo, Liu Peng, Su Yuwei, Jia Qingsong
Appl Opt. 2017 Jun 10;56(17):4934-4939. doi: 10.1364/AO.56.004934.
We study a passively mode-locked square-wave pulse (SWP) fiber laser with a nonlinear amplifying loop mirror in the cavity. The net dispersion of the cavity is about 0.68 ps and the SWP mode-locked fiber laser can be realized. The peak power of the SWP hardly varies and the pulse duration gets expanded with the increasing pump power. SWPs breaking in the low nonlinear cavity can be observed and the stable dual SWP can be achieved in the experiment. When the total pump power stays at 800 mW, the interval of dual pulses is 41 ns. The widths of dual SWPs are both 1.5 ns. The output power rises linearly with the increasing of the pump power, while the interval of dual SWPs is almost constant. Then, the physical mechanism of the SWP breaking and vector nature of the pulse are analyzed.
我们研究了一种腔内带有非线性放大环镜的被动锁模方波脉冲（SWP）光纤激光器。腔的净色散约为0.68 ps，可实现SWP锁模光纤激光器。随着泵浦功率的增加，SWP的峰值功率几乎不变，脉冲持续时间变宽。在实验中可以观察到低非线性腔内SWP的分裂，并可实现稳定的双SWP。当总泵浦功率保持在800 mW时，双脉冲的间隔为41 ns。双SWP的宽度均为1.5 ns。输出功率随泵浦功率的增加而线性上升，而双SWP的间隔几乎不变。然后，分析了SWP分裂的物理机制和脉冲的矢量性质。
