Numerical analysis of effective refractive index bio-sensor based on graphene-embedded slot-based dual-micro-ring resonator

Abstract

We propose a novel bio-sensor structure composed of slot dual-micro-ring resonators and mono-layer graphene. Based on the electromagnetically induced transparency (EIT)-like phenomenon and the light-absorption characteristics of graphene, we present a theoretical analysis of transmission by using the coupled mode theory and Kubo formula. The results demonstrate the EIT-like spectrum with asymmetric line profile. The mode-field distributions of transmission spectrum are obtained from 3D simulations based on finite-difference time-domain (FDTD) method. Our bio-sensor exhibits theoretical sensitivity of 330 nm/RIU, a minimum detection limit of [Formula: see text] RIU, the maximum extinction ratio of 4.4 dB, the quality factor of [Formula: see text] and a compact structure of [Formula: see text]. Finally, the bio-sensor’s performance is simulated for glucose solution. Our proposed design provides a promising candidate for on-chip integration with other silicon photonic element.