On the electric field enhancement and performance of SPR gas sensor based on graphene for visible and near infrared

We propose a high performance surface plasmon resonance (SPR) affinity gas sensor based on graphene on Ag in visible and near infrared. Proposed sensor configuration has been optimized for maximum surface plasmon field at the sensing layer interface. The field intensity enhancement factor at sensing layer interface is found to be higher than that of silicon over layer on Ag thereby increasing the imaging sensitivity by 340%, 120% and 82% and detection accuracy by 440%, 150% and 100% as compared to Si on Ag configuration at λ = 653 nm, λ = 850 nm and λ = 1000 nm respectively. The performance of the sensor is found to be high over a broad refractive index range (1.0000-1.0008) of gaseous analyte with sensor resolution of 8 × 10−5 RIU and 2 × 10−5 RIU at λ = 653 nm and λ = 1000 nm respectively. We believe the proposed SPR based gas sensor configuration will open a new route for efficient gas sensing by riding on the advantage of graphene and latest nanofabrication techniques.