This paper has designed a D-shaped photonic crystal fiber filter based on surface plasmon resonance. The single-polarization filtering performance is analyzed systematically by the finite element method. It is found that the structural optimization process will modify the refractive index of the fundamental mode and the surface plasmon polarization mode, which results in a shift of the resonance wavelength. The proposed filter is able to indicate the wavelength-tunable function in the ranges of 1250–1350 nm and 1550–1750 nm by two methods. Moreover, at the communication windows of 1310 nm and 1550 nm, the corresponding filtering bandwidths are 170 and 550 nm, respectively. The flow chart of filter preparation reported in the study is promising for use in the field of optical devices.

中文翻译：

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宽带宽波长D型光子晶体光纤滤光片的分析

本文设计了一种基于表面等离子体共振的D形光子晶体光纤滤波器。通过有限元方法对单极化滤波性能进行了系统的分析。发现结构优化过程将改变基本模式和表面等离子体激元偏振模式的折射率，这导致谐振波长的偏移。所提出的滤光片能够通过两种方法指示波长在1250–1350 nm和1550–1750 nm范围内的波长可调功能。此外，在1310 nm和1550 nm的通信窗口处，相应的滤波带宽分别为170和550 nm。该研究报告的滤光片制备流程图有望用于光学设备领域。