Abstract
Abstract
Herein, a plasmonic refractive index (RI) sensor based on a metal–insulator–metal waveguide coupled with maze-shaped resonators is proposed and numerically investigated using finite element method. Various geometrical parameter impacts on the transmission spectrum are examined to optimize the sensor’s performance. Additionally, the effect of using SiO2 as a dielectric material instead of air has been investigated. The proposed sensor can achieve maximum RI sensitivity, figure of merit, and sensing resolution of 3340 nm RIU−1, 143.33 RIU−1, and 2.99 × 10−6 RIU, respectively, in the 500–3500 nm wavelength range. The designed structure is investigated for potential applications in different biological fields, including detecting cancer cells, determining blood hemoglobin (HB) levels, and glucose concentrations. This sensor can detect MCF-7 cancer cells with a maximum sensitivity of 3543 nm RIU−1 and can achieve the sensitivity of 0.407 nm·l g−1 for glucose concentration and 3329.41 nm RIU−1 for blood HB level. The structure presented in this study has promising specifications, making it suitable for use in optical integrated circuits, particularly in highly sensitive sensors.