Sensitivity Enhanced by MoS2-Graphene Hybrid Structure in Guided-Wave Surface Plasmon Resonance Biosensor

Compared with surface plasmon resonance (SPR) biosensor, guided-wave surface plasmon resonance (GWSPR) biosensor has a higher sensitivity. In order to further enhance the sensitivity of the GWSPR biosensor, the MoS2-graphene hybrid structure is proposed to cover on the surface of the thin silicon film. It is demonstrated that the sensitivity of the proposed biosensor configuration can be doubled by using optimized MoS2-graphene hybrid structure. By analyzing the electric field distributions with the proposed GWSPR biosensor, it is shown that the electric field intensity has a dramatic change with a slight change in refractive index of sensing medium, and it also means that the biosensor is sensitive to detect the analytes. Moreover, the proposed GWSPR biosensor has a wide detection range of refractive index of sensing medium, and the sensitivity is increased with the refractive index of sensing medium increasing.