Based on the lack of sensors for high concentration methane in life, the present study introduces a new type of D-shaped photonic crystal fiber utilizing surface plasmon resonance effects, designed for the detection of high concentrations of methane. Differing from conventional D-type photonic crystal fiber, this model coats a gold film on an open-loop channel for excitation. Through the finite element method analysis, the simulation results demonstrate, this sensor exhibits an effective scope of 1.24–1.32 for the refractive index of analyte. The escalation of the analyte's refractive index leads to a gradual intensification of the loss peak within the spectrum. And then remains stable. The sensor demonstrates excellent performance at a refractive index of 1.32, delivering a maximum sensitivity of 22000 nm/RIU and a resolution of 4.55∙10 RIU. Achieving the methane concentration detection in the range of 27%–45% was made possible through the establishment of the relationship between refractive index and methane concentration. According to simulation results, within the concentration scope of 29%–39%, the maximum detection sensitivity for methane can reach 700 nm/%. The sensor has simple structure and excellent performance. We conducted an analysis of how structural parameters impact the resonance spectrum with the goal of optimization. The outstanding sensing performance makes it more competitive in the field of methane concentration detection, and it is not only used for methane detection.

中文翻译：

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利用表面等离子体共振原理的高灵敏度、D形截面U形通道的甲烷浓度传感器

鉴于生活中缺乏高浓度甲烷传感器，本研究引入了一种利用表面等离子体共振效应的新型D形光子晶体光纤，设计用于检测高浓度甲烷。与传统的D型光子晶体光纤不同，该模型在开环通道上涂覆金膜进行激发。通过有限元法分析，仿真结果表明，该传感器对分析物的折射率表现出1.24~1.32的有效范围。分析物折射率的升高导致光谱内损耗峰逐渐增强。然后保持稳定。该传感器在折射率为 1.32 时表现出优异的性能，最大灵敏度为 22000 nm/RIU，分辨率为 4.55∙10 RIU。通过建立折射率与甲烷浓度之间的关系，实现了27%~45%范围内的甲烷浓度检测。根据模拟结果，在29%~39%的浓度范围内，甲烷的最大检测灵敏度可达700 nm/%。该传感器结构简单，性能优良。我们对结构参数如何影响共振谱进行了分析，以达到优化的目的。出色的传感性能使其在甲烷浓度检测领域更具竞争力，并且不仅仅用于甲烷检测。