报道了一种宽调谐单纵模光纤激光器。该光纤激光器采用环行器确保腔内激光的单向传输, 可以有效消除空间烧孔效应;采用复合腔的Vernier效应选取单个纵模;利用未泵浦掺杂光纤的可饱和吸收效应, 有效抑制光纤激光器的跳模现象;同时, 利用自行研制的光纤光栅调谐装置, 调谐激光器振荡波长。测试结果表明, 该单纵模光纤激光器输出激光的线宽为0.7 kHz, 功率为10 mW, 波长调谐范围为20 nm, 且调谐过程中始终保持单纵模特性。

A wide-tunable single-longitudinal-mode fiber laser based on ring cavity structure was presented. The unidirectional propagation of light controlled by the circulator in the ring cavity can eliminate the spatial hole burning effect effectively. For realizing single-longitudinal-mode operation in fiber laser, the compound cavities designed based on Vernier effect were adopted. For suppressing the mode hopping, the saturable absorber effect of an unpumped doped fiber was considered. Meanwhile, the fiber Bragg grating filter with a widely tuning range was used to select oscillation wavelength. With these configurations, a stable single-longitudinal-mode erbium-doped fiber laser with 10 mW output power, 0.7 kHz linewidth and 20 nm tuning range was achieved.