报道了一种结构简单、波长稳定可调的被动锁模环形腔掺铒光纤激光器。利用非线性偏振旋转效应作为等效可饱和吸收体实现自起振被动锁模, 通过使用光纤偏振控制器和偏振相关光隔离器作为波长调谐器件, 在输出端使用输出耦合器为工作波长在1550±50 nm的宽带耦合器, 实现了光纤激光器的输出锁模脉冲激光中心波长较宽范围可调谐。实验上获得了低阈值自起振, 重复频率为10.23 MHz, 中心波长在1548.64～1600.24 nm内连续可调, 边模抑制比大于44 dB的超短脉冲输出。

A simple,stable wavelength tunable passively mode-locked erbium-doped fiber ring laser is reported. The nonlinear polarization rotation effect is used, as equivalent saturable absorber, to achieve the self-starting mode-locking in the laser. The wavelength tuning can be realized by simply rotating the orientation of polarization controllers. The output of the laser is taken via a wideband coupler, whose operating wavelength is 1550±50 nm. Experimentally, low self-starting threshold mode-locked pulses at 10.23 MHz repetition rate were obtained. The output wavelength was continuously tunable from 1548.64 nm to 1600.24 nm, and the side-mode suppression ratio was beyond 44 dB.