Plasmonic sensor based on microstructure PCF: performance analysis with outside detecting approach

In this paper, a novel microstructure photonic crystal fiber (MC-PCF)-surface plasmon resonance sensor is presented and developed using the finite element method with perfectly matched layer boundary condition. The sensor performance in terms of wavelength sensitivity (WS), amplitude sensitivity (AS), and figure of merit (FoM) is quantitatively examined using an external sensing technique with an optimal thickness of 40 nm of chemically stable gold. Finer mesh analysis is also used for modal analysis. At this optimized gold thickness, the highest recorded WS of 92,000 nm per RIU and AS of 1080 per RIU at a detecting range of 1.33–1.38 RIU are obtained. Within this detecting range, the sensor also has a strong linear fit and a FoM of 348.15 per RIU, respectively. Because of its high sensitivity and FoM, the suggested sensor might be a viable competitor in detecting the analyte refractive index. Finally, to demonstrate the performance capability of our proposed sensor, all performance parameters were compared to previously published studies.