High-sensitivity surface plasmon resonance refractive index sensor with high resolution based on D-shaped photonic crystal fiber

A high-sensitivity refractive index (RI) sensor based on surface plasmon resonance (SPR) effect in D-shape photonic crystal fiber (PCF) is presented and discussed by the finite element method (FEM). The designed PCF is polished to enhance the interaction of the evanescent field with analyte, improving the sensing performance. Simulation results indicate that the sensor has a sensing range from 1.30 to 1.35. The maximum spectral sensitivity of 18,139.37 nm/RIU and a high resolution of 5.5 x 10(-6)RIU can be obtained at 1.35. The average spectral sensitivity is 10683.3 nm/RIU. For the purpose of optimizing sensing performance, the effects of the structure parameters on the resonant spectra are also studied. The advantage of the sensor is that a simple structure with the same diameter can be used to achieve high refractive index sensitivity and resolution.