A theoretical analysis on sensitivity improvement of an SPR refractive index sensor with graphene and barium titanate nanosheets

Abstract

The sensitivity of the surface plasmons resonance (SPR) refractive index sensor is investigated using angle interrogation. The modified configuration is presented to enhance the performance of the sensor. A multilayer SPR Sensor is proposed with the BK7 prism, silver (Ag), barium titanate, and graphene sheets. The thickness of both the Ag layer is 50 nm and 10 nm, respectively. A layer of BaTiO3 is sandwiched between two thin layers of Ag. The sensitivity is high as 280°/RIU has been achieved with four thin layers of BaTiO3 and mono layer of graphene, which is 108 % higher than the conventional sensor. The graphene layer is used as a bio-compatible reagent, which improves the sensitivity of the sensor. The investigated sensor is susceptible to a 1.358 refractive index. This sensor has the potential for biomedical and biochemical sensing applications.