Abstract We demonstrate a passively Q-switched erbium-doped fiber laser (EDFL) with a birefringent Sagnac loop mirror (SLM) that combines the gain spectrum enables the laser to operate in tunable and switchable single/dual-wavelength states. When the pump power is up to 300 mW, the stable Q-switched pulse with the repetition rate and pulse duration of 58.57 kHz and 17.07 μs is achieved by properly adjusting the polarization controller-1 (PC-1) in the cavity. Meanwhile, the tunable and switchable single wavelength and dual wavelength regime is achieved by modulating the PC-2 in SLM, whose tunable ranges of single and dual wavelength are 3.27 nm and 1.69 nm, respectively. The proposed laser may meet the great application demands in nonlinear optics at 1.5 μm band.

中文翻译：

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单/双波长可切换可调无源调Q掺铒光纤激光器

摘要 我们展示了一种被动调 Q 掺铒光纤激光器 (EDFL)，它具有双折射萨格纳克环镜 (SLM)，结合增益光谱使激光器能够在可调谐和可切换的单/双波长状态下运行。当泵浦功率达到300 mW时，通过适当调整腔内的偏振控制器-1（PC-1），可以实现重复频率和脉冲持续时间为58.57 kHz和17.07 μs的稳定调Q脉冲。同时，可调谐和可切换的单波长和双波长方案是通过调制 SLM 中的 PC-2 实现的，其单波长和双波长的可调范围分别为 3.27 nm 和 1.69 nm。所提出的激光器可以满足1.5 μm波段非线性光学的巨大应用需求。