We report the experimental observation of a novel transmission phenomenon in optical long-haul communication systems. Unpolarized ASE depolarizes via nonlinear fiber interactions a cw laser light during their copropagation which leads to small but measurable ultrafast polarization state fluctuations at the fiber output. We provide a phenomenological approach and a theory that qualitatively corroborates our experimental results. One of our major findings suggests that the applicability of the often used Manakov equation needs to be scrutinized for highly accurate studies of nonlinear polarization state evolutions in noisy environments. The described phenomenon leads to a qualitatively different microscopic understanding of nonlinear light propagation in fiber and can contribute toward an explanation for today’s commonly perceived gap between simulated and experimentally obtained system performance in optical data transmission.

中文翻译：

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光通信光纤中的光的非线性去极化

我们报告在光学远程通信系统中的一种新型传输现象的实验观察。非偏振ASE在连续传播过程中通过非线性光纤相互作用使连续波激光消偏振，从而导致光纤输出处的微小但可测量的超快偏振态波动。我们提供一种现象学方法和一种理论，从质量上证实了我们的实验结果。我们的主要发现之一表明，对于在嘈杂环境中进行非线性极化态演化的高精度研究，需要仔细研究经常使用的Manakov方程的适用性。