A photonic quasi-crystal fiber (PQF) methane sensor based on surface plasmon resonance (SPR) is designed and described. The double-side polished six-fold photonic quasi-crystal fiber coated with a silver film produces enhanced SPR effects and sensitivity. A nanostructured thin film with cryptophane-E-doped polysiloxane is deposited on silver as the methane-sensitive surface layer and to mitigate oxidation of silver. The sensor is analyzed and optimized numerically by the full-vector finite element method. For methane concentrations in the range of 0% to 3.5%, the maximum sensitivity of the sensor is 8 nm/%, and the average sensitivity is 6.643 nm/%. Compared to traditional gas sensors, this sensor provides accurate sensing of methane besides offering advantages such as the low cost, miniaturized size, online monitoring, and immunity to electromagnetic field interference.

中文翻译：

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基于表面等离子体共振的光子准晶光纤构成的高灵敏度甲烷传感器

设计并描述了一种基于表面等离子体共振 (SPR) 的光子准晶体光纤 (PQF) 甲烷传感器。涂有银膜的双面抛光六倍光子准晶体光纤产生增强的 SPR 效果和灵敏度。带有隐甲-E 掺杂聚硅氧烷的纳米结构薄膜沉积在银上，作为对甲烷敏感的表面层，以减轻银的氧化。采用全矢量有限元法对传感器进行数值分析和优化。对于0%~3.5%范围内的甲烷浓度，传感器的最大灵敏度为8 nm/%，平均灵敏度为6.643 nm/%。与传统的气体传感器相比，该传感器除了具有低成本、小型化、在线监测、