Nanoscale Refractive Index Sensors Based on Fano Resonance Phenomena

In this paper, a new refractive index sensor based on Fano resonance is introduced. It mainly composed of two parts: metal–insulator–metal as base waveguide and an annular resonant cavity with double notch convex circle coupling structure. The sensing characteristics the design are investigated via finite element calculations. influence remaining structure parameters system’s performance relationship between wavelength corresponding to trough also investigated. Furthermore, applied sensors, resulting in type sensitivity 2740 nm/RIU figure merit 52.69.