Tunable photonic crystal fiber polarization splitter is proposed and analyzed. The proposed splitter has a dual asymmetric cores where one core is only filled with a nematic liquid crystal (NLC). The birefringence is also increased between the two polarized modes due to the NLC material which improves the splitting performance. The coupling between the two asymmetric cores occurs at a specific wavelength which can be controlled by the NLC material. Additionally, the splitting between the two polarized modes can be tuned by rotating the NLC molecules using an external electric field. Further, the matching wavelength where the power coupling occurs between the two asymmetric cores can be controlled thermally due to the NLC dependence on the temperature. The analysis of the proposed splitter is carried out using full vectorial finite difference method. The reported polarization splitter has a compact device length of 602 µm at λ = 1.3 μm with high wavelength selectivity. In addition, large bandwidth of 60 nm is obtained with crosstalk lower than − 20 dB which ensures the superiority of the reported device.

中文翻译：

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基于非对称双芯液体光子晶体光纤的可调谐偏振分束器

提出并分析了可调谐光子晶体光纤偏振分束器。建议的分路器具有双不对称核心，其中一个核心仅填充向列液晶 (NLC)。由于 NLC 材料提高了分光性能，两种偏振模式之间的双折射也增加了。两个不对称纤芯之间的耦合发生在可由 NLC 材料控制的特定波长。此外，可以通过使用外部电场旋转 NLC 分子来调整两种极化模式之间的分裂。此外，由于 NLC 对温度的依赖性，可以热控制在两个不对称纤芯之间发生功率耦合的匹配波长。所提出的分离器的分析是使用全矢量有限差分法进行的。报道的偏振分束器在 λ = 1.3 μm 处具有 602 μm 的紧凑器件长度，具有高波长选择性。此外，获得了 60 nm 的大带宽，串扰低于 - 20 dB，确保了所报告设备的优越性。