被动锁模光纤激光器中窄带滤波器对多脉冲产生的影响研究

通过实验研究了在被动锁模掺铒光纤环形激光器中加入窄带滤波器对多脉冲产生的影响.在激光器的腔内插入一个窄带光纤布拉格光栅（FBG），限制激射带宽，可以在低阈值的情况下产生多脉冲.多脉冲的个数取决于泵浦功率的设置，激光器输出脉冲的个数可以分立可调.另外，实验中也观察到多脉冲的混沌态.数值模拟进一步证实了实验结果.实验表明，窄带滤波器可以加强多脉冲的产生，这有助于进一步理解光纤激光器中多脉冲的形成机制.

Effect on Multi-pulse of a Narrow-band Filter in a Passively Mode-locked Fiber Ring Laser

Multi-pulse generation based on a narrow-band filter in a passively mode-locked erbium-doped fiber ring laser is investigated experimentally. The low threshold multi-pulse is easily achieved by inserting a narrow-band fiber Bragg grating (FBG) filter into the laser ring cavity to limit the lasing bandwidth. Depending on the pump power settings, the number of output pulses can be discretely tuned one by one. Moreover, the chaotic state of multi-pulse operation is also observed. The experimental results are further confirmed by the numerical simulations, which prove that a narrow-band filter could greatly enhance the multi-pulse generation.