基于金银复合膜的光子晶体光纤表面等离子体共振传感器

Photonic crystal fiber surface plasmon resonance sensor based on gold silver composite film

为了优化基于D型光子晶体光纤单层金属膜折射率传感器的性能,提出了一种基于金银复合膜的D型光子晶体光纤表面等离子体共振(PCF-SPR)效应传感器.该传感器具有结构简单、灵敏度高、能有效减少银的氧化、半高宽窄等优点.利用有限元法对所提出的传感器结构进行了模态分析,以评估该传感器的各项参数.仿真结果表明:在纤芯小空气孔直径为0.20μm、大空气孔直径为0.75μm、气孔间距为2.00μm、金膜的厚度为15 nm、银膜的厚度为30 nm时,最大折射率灵敏度为6400.00 nm/RIU,分辨率为1.56×10^(-6) RIU;在相同结构中,相比于单层金膜的折射率灵敏度提高了120%,分辨率提高了95%.该传感器可应用于高灵敏度折射率传感或温度传感等领域.

In order to optimize the performance of single-layer metal film refractive index sensor based on D-type photonic crystal fiber,a D-type PCF-SPR effect sensor based on gold silver composite film was designed.The proposed sensor added advantages of simple structure,high sensitivity,effective reduction of silver oxidation and small FWHM.The modal analysis of the sensor structure was carried out by using the finite element method to evaluate the parameters of the sensor.The simulation results showed that the diameter of pores in the core was 0.20μm,the diameter of air pores was 0.75μm,and the air hole spacing was 2.00μm.The thickness of gold film was 15 nm,and the thickness of silver film was 30 nm.The maximum refractive index sensitivity was 6400.00 nm/RIU and the resolution was 1.56×10^(-6) RIU;Compared with the single-layer gold film,the refractive index sensitivity was improved by 120%and the resolution was improved by 95%.The proposed sensor could be used in the field of high sensitivity refractive index sensing or temperature sensing.