In this paper, to the best of our knowledge, a new type of hollow-core anti-resonant fiber (HC-ARF) design using hybrid silica/high-index material (HIM) cladding is presented for single-polarization, high-birefringence, and endlessly single-mode operation at 2 μm wavelength. We show that the inclusion of a HIM layer in the cladding allows strong suppression of $x-$ polarization, while maintaining low propagation loss and single-mode propagation for $y-$ polarization. The optimized HC-ARF design includes a combination of low propagation loss, high-birefringence, and polarization-extinction ratio (PER) or loss ratio of 0.02 dB/m, 1.2 $\times \, 10^{-4}$ , and >550 respectively, while the loss of the $x-$ polarization is >20 dB/m. The proposed fiber may also be coiled to small bend radii while maintaining low bend-loss of $\approx$ 0.01–0.1 dB/m, and can potentially be used as polarization filter based on the different gap separations and bend conditions.

中文翻译：

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2 μm 单偏振、单模混合空心抗谐振光纤设计

在本文中，据我们所知，提出了一种采用混合二氧化硅/高折射率材料（HIM）包层的新型空心抗谐振光纤（HC-ARF）设计，用于单偏振、高双折射，以及在 2 μm 波长下的无限单模操作。我们表明，包层中包含 HIM 层可以强烈抑制$x-$ 偏振，同时保持低传播损耗和单模传播$y-$ 极化。优化的 HC-ARF 设计结合了低传播损耗、高双折射和偏振消光比 (PER) 或损耗比 0.02 dB/m、1.2$\次 \, 10^{-4}$ ，和> 550分别，而损失$x-$ 极化>20 dB/m。所提出的光纤还可以盘绕成小弯曲半径，同时保持低弯曲损耗$\大约$ 0.01–0.1 dB/m，并且可以根据不同的间隙间隔和弯曲条件用作偏振滤波器。