We present the experimental investigation of a dual-wavelength passively mode-locked Er-doped fiber laser with strict polarization control. The configuration includes a double-pass amplifier with a Faraday mirror and twisted fiber. We observe that including double-twist fiber cancels circular and linear birefringence and allows obtaining dual-wavelength emission varying the losses in the cavity. In contrast, results including single-twist fiber which only emits single-wavelength due to large circular birefringence.

中文翻译：

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无光谱滤波器腔中的双波长锁模掺Er光纤激光器

我们目前进行严格偏振控制的双波长无源锁模掺Er光纤激光器的实验研究。该配置包括一个带法拉第镜和双绞光纤的双通放大器。我们观察到，包括双捻光纤消除了圆形和线性双折射，并允许获得改变腔中损耗的双波长发射。相反，结果包括由于大的圆形双折射而仅发射单波长的单捻光纤。