On the sensitivity-enhancement in plasmonic biosensor with photonic spin Hall effect at visible wavelength

Highlights: • Explore the ability of BlueP/MoS₂ heterostructure, and graphene to enhancing the PSHE. • The maximum $A_w{\delta }_{\pm }^H$ 777.6 µm has been obtained for the H polarization. • $A_w{\delta }_{\pm }^H$ decreases due to increases the radiation damping as increases in graphene layers. Photonic spin Hall effect based surface plasmon resonance sensor is reported to examine the sensitive detection of the biomolecules. From the obtained results, it is observed that the transverse spin-dependent shifts (SDS) can be modified if the refractive index in the sensing layer is changed by an extremely small amount. The results lead to a sensitivity of the proposed sensor as 1.555 × 10⁵ μm/RIU, which corresponds to maximum SDS of 777.6 µm at an optimal amplified angle = 0.1°. The above-mentioned sensitivity is more than 1.4 times the sensitivity achievable with the Au-graphene plasmonic sensor design.