Hybrid plasmonic label-free multi-analyte refractive index sensor

Abstract

We propose a label-free refractive index sensor based on hybrid plasmonic resonator which consists of silver split-ring resonator and photonic waveguide. The finite difference time domain evaluation of the design exhibit strong field confinement at the center of the ring and introduces tunable and sensitive notches in the transmission spectrum. The planar tunable architecture which performs well over the range of micro fluid detection, holds the promise of developing multi-analyte label-free biosensors and compactness towards a complete on-chip integrated sensing system. The performance of the proposed refractive index sensor is evaluated by placing different analytes such as saline water and ethanol at the center of the hybrid plasmonic ring which exhibits sensitivity of 847.50 nm·RIU−1 with a figure of merit of 563.25 RIU−1.