This paper deals with the development and analysis of D-Shaped photonic crystal fiber (PCF) biosensors using surface plasmon resonance (SPR). A thin metal layer is deposited on the outer flat surface of the PCF that behaves as the plasmonic material. Analyte is filled in the outermost peripheral region of metal layer. Finite element method (FEM) with perfectly matched layer (PML) is applied to analyze the proposed sensors. Mode analysis is performed on the proposed structures to evaluate various parameters of SPR-based PCF sensors. Three D-shaped PCF structures have been proposed with silver (Ag), gold (Au) and two-half layers of both (Ag-Au) on its flat surface. The first two structures are analyzed to the range of wavelength where the SPR will occur to facilitate understanding of the third structure. It is observed that the structures with one metal have only one sensitive plasmonic peak whereas the structure with two metal layers has two sensitive plasmonic peaks, making it suitable candidate for two-molecule sensing present in a sample analyte. Good sensitivities and resolutions are achieved for both plasmonic peaks.

中文翻译：

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具有空间分布双金属层的D型光子晶体光纤表面等离子共振生物传感器

本文利用表面等离振子共振（SPR）技术研究了D形光子晶体光纤（PCF）生物传感器的开发和分析。薄金属层沉积在PCF的外部平坦表面上，该表面充当等离子体材料。分析物填充在金属层的最外围区域。应用具有完美匹配层（PML）的有限元方法（FEM）来分析所提出的传感器。对建议的结构执行模式分析，以评估基于SPR的PCF传感器的各种参数。已经提出了三种D形PCF结构，在其平坦表面上具有银（Ag），金（Au）和两半层（Ag-Au）。将前两个结构分析到发生SPR的波长范围，以便于理解第三个结构。观察到，具有一种金属的结构仅具有一个敏感的等离激元峰，而具有两个金属层的结构具有两个敏感的等离激元峰，使其适合用于样品分析物中存在的两分子感测。两个等离激元峰均具有良好的灵敏度和分辨率。