▎ 摘　　要

This article illustrates a graphene tri sheets based surface plasmon resonance (SPR) biosensor. The exciting configuration consists of Gold (Au), graphene, prism (SF11 glass) and sensing medium. The angular interrogation scheme is basically utilized owing to inspect the light reflection from the sensor. For sake of the augmentation of sensor sensitivity (S), signal to noise ratio (SNR), quality factor (QF), first of all, the impact of adding graphene layer is investigated and then the number of graphene layers are optimized to tri layers. According to that tri sheets, the SPR curves are sketched and comparison of sensor sensitivity, SNR, the quality factor is made among the existing works. It is audited that an extraordinary improvement of sensitivity to 121.67 degrees RIU-1. The most effective graphene layers states with improved SNR of 2.21 and QF of 36.87 RIU-1 respect conventional SPR sensor. After then, the electric field intensity on implanting graphene sheet is analyzed by incorporating the finite difference time domain (FDTD) method by applying the Opti FDTD multiphysics commercial software environment. The proposed design bears the advantages of high sensitivity, QF and SNR comparing with the existing sensors along with simple stricture, no need of plasmonic coatings of other dielectrics, compactness, light weight, real time fabrication flexibility due to avoid multi materials optical structure.