提出一种基于法布里-珀罗滤波器和饱和吸收体的单纵模掺铥光纤激光器。利用窄带法布里-珀罗滤波器和未泵浦掺铥光纤的饱和吸收体来实现激光的单纵模输出。在室温条件下，实现中心波长1941.6 nm、信噪比32 dB的稳定激光输出。通过100 min的连续观测，激光器的中心波长偏移小于0.04 nm，激光输出功率抖动小于1.5 dB，证明单纵模掺铥光纤激光器可以在一段时间内稳定工作。
A single-longitudinal-mode thulium-doped fiber laser using Fabry-Perot (F-P) filter and saturable absorber is proposed and experimentally demonstrated at the 2 μm band. In the structure, the combination of a narrowband F-P filter and a section of unpumped thulium-doped fiber ensures the single-longitudinal-mode lasing operation. A stable lasing operation is obtained at room temperature, with the central wavelength of 1941.6 nm and the optical signal-to-noise ratio of 32 dB. For an experimental period of 100 min, the output power fluctuates less than 1.5 dB and the center wavelength shifts less than 0.04 nm, indicating that the single-longitudinal-mode thuliumdoped fiber laser possesses good long-term stability.
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