Glucose Level Measurement Using Photonic Crystal Fiber–based Plasmonic Sensor

In this study, we demonstrate the design of a photonic crystal fiber (PCF)-based plasmonic sensor to measure the glucose level of urine. The sensor is designed by placing a small segment of PCF between a lead-in and a lead-out single-mode fiber. We utilize the finite element method to simulate the proposed plasmonic sensor for the measurement of glucose level in urine. To offer external sensing, the cladding layer of the PCF was coated by a thin layer of gold where the gold-coated PCF was immersed in the urine sample. As a result, the urine can easily interact with the plasmonic layer of the sensor. In the outermost laser of the PCF, we considered a perfectly matched layer as a boundary condition. The simulation results confirm excellent wavelength and amplitude sensitivities where the maximum wavelength sensitivity was 2500 nm/RIU and amplitude sensitivity was 152 RIU−1 with a sensing resolution of 4 × 10−6. For optimization of the plasmonic sensor, we varied the physical parameters of the cladding air holes and the thickness of the gold layer during the simulation. We strongly believe that the proposed plasmonic sensor will play a significant role to pave the way for achieving a simple but effective PCF-based glucose sensor.