A long-term stable single-longitudinal-mode (SLM) all polarization-maintaining (PM) compound-ring cavity fiber laser is reported. The results show that the PM fiber's strong ability to resist the environment disturbance allows finely designing the length of each secondary cavity in real time according to the main cavity under the laboratory environment, and then the effective longitudinal mode spacing can be sufficiently increased by accurately using the Vernier effect, so that the mode-hopping can be effectively suppressed. Furthermore, the temperature compensation is used for asynchronously fine-adjusting each cavity length to follow the Vernier effect requirement more strictly. The mode-hopping-free SLM operation time of the packaged laser reaches 11 h. As far as we know, this is the longest SLM free running time of ring cavity fiber laser to date. The optical signal to noise ratio of the laser reaches 77 dB and the linewidth is less than 850 Hz with up to 50 mW maximum output power.

中文翻译：

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使用保偏光纤的长期稳定850Hz线宽单纵模环腔光纤激光器

报道了一种长期稳定的单纵模 (SLM) 全保偏 (PM) 复合环腔光纤激光器。结果表明，保偏光纤抗环境扰动能力强，可以在实验室环境下根据主腔实时精细设计每个次腔的长度，然后通过准确使用可以充分增加有效纵模间距。游标效应，从而有效抑制跳模。此外，温度补偿用于异步微调每个腔长，以更严格地遵循游标效应要求。封装激光器的无跳模SLM工作时间达到11小时。据我们所知，这是迄今为止环形腔光纤激光器最长的SLM自由运行时间。激光器的光信噪比达到77 dB，线宽小于850 Hz，最大输出功率可达50 mW。