Chalcogenide prism and graphene multilayer based surface plasmon resonance affinity biosensor for high performance

Reflectivity optimization of the SPR graphene sensor

“…The latter becomes different of the wave vector tangential component of incident light and hence the resonance condition is not fulfi lled (i.e., SPs become damped) [10,13]. To minimize this effect, we optimize the silver layer thickness that decreases when the number of graphene layers increases (see Table 1).…”

“…The noble metals [7,8] as Ag and Au are more commonly used to support the propagation of surface plasmon polariton waves (SPP) at visible light wavelengths [4,9,10]. How-ever, silver substrates seems to be the most appealing, because it provides in the metal-sensing layer interface a high value of electric fi eld enhancement with low imaginary part of refractive index [11].…”

Graphene–MoS2 hybrid nanostructures enhanced surface plasmon resonance biosensors

“…However, it was reported that graphene-based SPR sensors possessed the highest detection sensitivity when the total number of graphene layers deposited on the metallic SPR sensing substrate (50 nm) is larger than 10. Even with such thick layers of graphene on the SPR substrate, the sensitivity enhancement factor has only increased from 1.25 to 2, which is considered to be an incremental improvement for the sensitivity of the SPR biosensor [22,[25][26][27][28].…”

Optical Field-Enhancement and Subwavelength Field-Confinement Using Excitonic Nanostructures

“…A variety of alternative materials have been explored, including: doped semiconductors, 5 graphene, 6 chalcogenides, 7 tunable metal-semiconductor materials, 8,9 transparent conducting oxides, 10 heavily-doped conducting polymers, 11 and some nitrides, 12,13 among others. All of these materials yield a plasmonic response owing to the free charge-carriers they contain.…”