Graphene-MoS2 heterostructure based surface plasmon resonance biosensor

In this paper, a graphene-MoS
₂
heterostructure biosensor with silver (Ag) substrate based on the surface plasmon resonance (SPR) principle is presented. The biosensor is designed to sense at least monolayer single stranded DNA (ssDNA) which has a thickness of 3.2 nm. The design process is performed according to the best minimum light intensity conception with Transfer Matrix Method (TMM). The background substrate formed by Ag film-MoS
₂
-graphene is simulated numerically by increasing the number of graphene. During this process, the thickness of Ag-film is optimized by taking the light intensity into consideration. The results show that the sensitivity of the biosensor can be enhanced with the number of the graphene layers. The shift in resonance angle, i.e sensitivity, improves at the ratio of 13% with 5-layer graphene.