Abstract In this work, multi-wavelength lasing in the S-band region using a Sagnac loop filter in a thulium-doped fluoride fiber laser (TDFFL) was demonstrated for the first time. The Sagnac loop served as a comb-like wavelength filter, while a 10-km long dispersion compensating fiber (DCF) was utilized to induce the four-wave mixing (FWM) effect in the cavity. The FWM effect was used to suppress mode competition in the TDFFL as well as to enhance the number of lasing lines. At its optimum polarization state, 17 stable lasing lines at peak powers of less than 10 dB from the highest peak power were observed, with these lasing lines having a uniform wavelength spacing of 0.23 nm. The multi-wavelength operation exhibited minimal wavelength drifts and power fluctuations of less than 0.01 nm and 1.2 dB respectively. A tunable dual-wavelength laser output was also demonstrated, with a constant wavelength spacing throughout the tuning range.

中文翻译：

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S波段四波混频辅助多波长和双波长掺铥氟化物光纤激光器

摘要 在这项工作中，首次展示了在掺铥氟化物光纤激光器 (TDFFL) 中使用 Sagnac 环路滤波器在 S 波段区域的多波长激光。Sagnac 环路用作梳状波长滤波器，而 10 公里长的色散补偿光纤 (DCF) 用于在腔内引起四波混频 (FWM) 效应。FWM 效应用于抑制 TDFFL 中的模式竞争以及增加激光线的数量。在其最佳偏振状态下，观察到 17 条稳定的激光线，其峰值功率与最高峰值功率相差小于 10 dB，这些激光线具有 0.23 nm 的均匀波长间隔。多波长操作表现出最小的波长漂移和功率波动，分别小于 0.01 nm 和 1.2 dB。