Opt Express. 2023 Feb 27;31(5):8998-9006. doi: 10.1364/OE.481788.
Bidirectional wavelength-tunable mode-locked fiber lasers have demands for many applications. In our experiment, two frequency combs from a single bidirectional carbon nanotube mode-locked erbium-doped fiber laser are obtained. Continuous wavelength tuning is demonstrated in the bidirectional ultrafast erbium-doped fiber laser for the first time. We utilized the microfiber assisted differential loss-control effect on both directions to tune operation wavelength and it presents different wavelength tuning performances in two directions. Correspondingly, the repetition rate difference can be tuned from 98.6 Hz to 32 Hz by applying strain on microfiber within 23 µm stretching length. In addition, a minor repetition rate difference variation of 4.5 Hz is achieved. Such technique may provide possibility to expand wavelength range of dual-comb spectroscopy and broad its application fields.
双向波长可调谐锁模光纤激光器在许多应用中都有需求。在我们的实验中，从单双向碳纳米管锁模掺铒光纤激光器中获得了两个频梳。首次在双向超快掺铒光纤激光器中演示了连续波长调谐。我们利用微光纤辅助的差分损耗控制效应在两个方向上调节工作波长，并且在两个方向上呈现出不同的波长调谐性能。相应地，通过在 23 µm 拉伸长度内对微光纤施加应变，可以将重复率差从 98.6 Hz 调谐到 32 Hz。此外，还实现了 4.5 Hz 的较小重复率差变化。这种技术可能为扩展双梳光谱的波长范围并拓宽其应用领域提供了可能性。
