Sensitivity Enhanced Dual-Core Photonic Crystal Fiber Surface Plasmon Resonance Sensor Based on Gold Film

In this paper, we proposed a dual-core D-shaped photonic crystal fiber surface plasmon resonance refractive index sensor based on gold film. The proposed sensor uses two symmetrical fiber cores for enhanced surface plasmon resonance coupling to obtain extremely high amplitude sensitivity. The influence of structural parameters on the sensing performance was investigated. According to the simulation results, the sensor has a superior performance, which achieved the ultra-high amplitude sensitivity of 7679.2 RIU-1, the high average amplitude sensitivity of 4557.5 RIU-1, the amplitude interrogation resolution of 1.30 x 10(-6) RIU, the maximum wavelength sensitivity of 39,000 nm/RIU, the wavelength interrogation resolution of 2.56 x 10(-6) RIU-1 in a refractive index detection range of 1.37-1.40, and the maximum figure of merit of 246 RIU-1. The proposed sensor has a broad prospect of application in biological, environmental, and chemical detection.