We report on the experimental realization of, to the best of our knowledge, the first green and orange passively mode-locked all-fiber lasers. Stable mode-locking in the burst-pulse status is achieved at the wavelengths of 543.3 nm and 602.5 nm. The figure-9 cavity comprises the fiber end-facet mirror, gain fiber (Ho3+:ZBLAN fiber or Pr3+/Yb3+:ZBLAN fiber), and fiber loop mirror (FLM). The FLM with long 460 HP fiber is not only used as an output mirror, but also acts as a nonlinear optical loop mirror for initiating visible-wavelength mode-locking. The green/orange mode-locked fiber lasers with the fundamental repetition rates of 3.779/5.662 MHz produce long bursts containing ultrashort pulses with the 0.85/0.76 GHz intra-burst repetition rates, respectively. The ultrashort intra-burst pulses stem from the dissipative four-wave-mixing effect in the highly nonlinear FLM as well as the intracavity Fabry–Perot filtering. Long bursts of 22.2/11.6 ns with ultrashort pulses of 87/62 ps are obtained in our experiment. The visible-wavelength passively mode-locked lasers in an all-fiber configuration and burst-mode would represent an important step towards miniaturized ultrafast fiber lasers and may contribute to the applications in ablation-cooling micromachining, biomedicine imaging, and scientific research.

中文翻译：

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543 nm 和 602 nm 被动锁模全光纤绿色/橙色激光器中的突发模式脉冲生成


据我们所知，我们报告了第一个绿色和橙色被动锁模全光纤激光器的实验实现。在543.3 nm和602.5 nm波长下实现了突发脉冲状态下的稳定锁模。 9字形腔体包括光纤端面镜、增益光纤（何3+ ：ZBLAN 光纤或普罗3+ /镱3+ ：ZBLAN 光纤）和光纤环镜（FLM）。具有 460 HP 长光纤的 FLM 不仅用作输出镜，而且还充当用于启动可见光波长锁模的非线性光学环镜。基本重复频率为 3.779/5.662 MHz 的绿色/橙色锁模光纤激光器可产生包含超短脉冲的长脉冲，其内脉冲重复频率分别为 0.85/0.76 GHz。超短内突发脉冲源于高度非线性 FLM 中的耗散四波混频效应以及腔内法布里-珀罗滤波。我们的实验获得了 22.2/11.6 ns 的长脉冲和 87/62 ps 的超短脉冲。全光纤配置和突发模式的可见波长被动锁模激光器将代表朝着小型化超快光纤激光器迈出的重要一步，并可能有助于烧蚀冷却微加工、生物医学成像和科学研究的应用。