Highly sensitive PCF-SPR sensor for simultaneous refractive index and temperature measurement over a broad range

Abstract Sensing bandwidth is one of the important reasons that limit the performance of dual-channel sensors. In order to develop dual-channel fiber sensors with wide sensing bandwidth, a D-type silver-based photonic crystal fiber (PCF) sensor based on surface plasmon resonance (SPR) is proposed and analyzed by finite element method (FEM). Silver was selected as the plasma material to excite the SPR, Zinc oxide (ZnO) and tungsten disulfide (WS 2 ) were coated on the surface of silver film to modulate the sensing bandwidth. At the same time, polymethyl methacrylate (PDMS) was coated on the surface of ZnO film to construct the temperature sensing channel. The sensing bandwidth of this sensor covers 600 to 1700 nm. Simulation results show that the maximum RI sensitivity reaches 18700 nm RIU −1 over the RI range of 1.35–1.42, while the maximum temperature sensitivity is 14.3 nm °C −1 over the temperature range of −10 °C–100 °C. The results indicate that the sensor significantly broadens the sensing bandwidth and can achieve high-sensitivity detection at high temperatures. It will have broad application prospects in fields such as industry, environmental monitoring and medical care.