Theoretical analysis of all-solid D-type photonic crystal fiber based plasmonic sensor for refractive index and temperature sensing

We propose an all-solid D-type photonic crystal fiber (PCF) based surface plasmon resonance sensor for simultaneous measurement of refractive index (RI) and temperature. The RI sensing portion is formed by coating the silver film on the plane of the D-type structure, and the temperature sensing portion is constructed by filling the silver nanowire and the liquid mixture (sensing medium) into the only orthogonally arranged hole in the PCF. This design can support two independent peaks with orthogonal polarizations which can be used to distinguish the RI and temperature changes. We investigate the coupling characteristic and sensing performance of the sensor, as well as the influence of the position of the silver nanowire in the air hole. The numerical results indicate that the maximal sensitivity in terms of RI units (RIU) is 10300 nm/RIU in the range of 1.41–1.42, and the maximal temperature sensitivity is 4.22 nm/°C in the range of −3 °C–15 °C with the volume ratio 6:4 in chloroform and ethanol mixture.