A new design of polarization-maintaining and spectral filtering negative curvature hollow-core fiber tailored for the telecommunication bands in the near-infrared region is presented. The optical fiber, consisting of a six-tube silica structure, incorporates vertically nested tubes anchored radially by a pole structure. By contrast, standard nested tubes in the horizontal direction form the asymmetric fiber structure, which encounters birefringence. This unique fiber design not only preserves the polarization states of light but also exhibits frequency selective transmission exclusively in the vertical direction due to the pole structure. Through fiber design optimization, a transmission loss below for spectrally filtered wavelengths is achieved, with birefringence on the order of 10 within the wavelength range of to . These results demonstrate significant improvements in terms of birefringence, distinct loss separation between horizontally and vertically polarized states, and a reduced number of spectrally filtered wavelengths compared to previously reported findings. The proposed fiber design holds untapped potential for applications requiring selective transmissions with specific polarization.

中文翻译：

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增强负曲率空心光纤的偏振保持和光谱过滤

提出了一种专为近红外区域电信频段定制的保偏和光谱滤波负曲率空心光纤的新设计。该光纤由六管二氧化硅结构组成，包含由杆结构径向锚固的垂直嵌套管。相比之下，水平方向的标准嵌套管形成不对称的光纤结构，会遇到双折射。这种独特的光纤设计不仅保留了光的偏振态，而且由于极结构，仅在垂直方向上表现出频率选择性传输。通过光纤设计优化，可实现低于光谱过滤波长的传输损耗，在 到 的波长范围内双折射约为 10。这些结果表明，与之前报道的结果相比，双折射、水平和垂直偏振态之间明显的损耗分离以及光谱过滤波长数量的减少方面都有显着改善。所提出的光纤设计对于需要特定偏振选择性传输的应用具有未开发的潜力。