Refractive index and temperature sensor based on dual-D-shapes photonic crystal fiber surface plasmon resonance

A dual-D-shapes photonic crystal fiber (PCFs) surface plasmon sensor structure is designed in this paper. The finite element method (FEM) is used to study the influence of air hole radius, metal thickness and gap between dual-D-shapes fibers on its sensing performance. In dual-D-shapes sensor, the maximum wavelength sensitivity is up to 12,600 nm/RIU in the RI range of 1.33–1.37, and corresponding resolution is 7.94 × 10–6 RIU−1. Comparing the performance of the single-D-shape PCF sensor, the PCFs sensor has distinct advantages concerning the wavelength sensitivity, resolution, and figure of merits (FOM), but these advantages are at the expense of the detection range. In addition, we also used the sensor to conduct temperature simulation test, and obtained the maximum temperature sensitivity of -6 nm/°C.