In this paper, a broadband single polarization photonic crystal fiber (PCF) filter around 1.55 μm is presented on account of surface plasmon resonance. The finite element method is used to investigate the performance of the filter, and the structure parameters’ influences on the performances of the filter are studied. Due to asymmetry which is caused by the pentagonal arranged cladding air holes, the confinement loss of the Y polarization core mode reaches to as high as 1751.05 dB/cm around 1.55 μm, while the loss for the X polarization mode is only 0.22 dB/cm. This indicates that a loss ratio of 7959.32 is achieved and the crosstalk value is up to 304.15 dB with 200 μm PCF around 1.55 μm. Moreover, the bandwidth of 20 dB crosstalk value is 1010 nm with a wavelength coverage from 1.39 to 2.40 μm. Numerical simulations also show that the designed filter has good tolerance to structural deformation. Therefore, the proposed pentagonal filter has great potentials in the application of broadband communication system.

中文翻译：

---

基于镀金和五边形结构的约1.55μm宽带单偏振光子晶体光纤滤波器

本文提出了一种基于表面等离子体激元共振的宽带单偏振光子晶体光纤（PCF）滤光片，滤光片的厚度约为1.55μm。利用有限元方法研究了滤波器的性能，研究了结构参数对滤波器性能的影响。由于五边形排列的包层气孔造成的不对称性，Y极化芯模的约束损耗在1.55μm左右高达1751.05 dB / cm，而X极化模的损耗仅为0.22 dB / cm 。这表明在200μmPCF约为1.55μm的情况下，实现了7959.32的损耗比，串扰值高达304.15 dB。此外，20 dB串扰值的带宽为1010 nm，波长覆盖范围为1.39至2.40μm。数值模拟还表明，所设计的过滤器对结构变形具有良好的耐受性。因此，提出的五边形滤波器在宽带通信系统的应用中具有很大的潜力。