Effect of MoS2 layer on the LSPR in periodic nanostructures

Abstract In this work, we propose a new configuration of the localized surface plasmon resonance (LSPR), based on MoS 2 hybrid structures for ultrasensitive biosensing applications. The plasmonic resonances are widely used in bimolecular detection and continue to be an active network because of the rich variety of surface configurations and measurement donations. The present work studies the interaction of gold nanoparticles with a MoS 2 film. MoS 2 is used as a thin spacer between the gold nanoparticles and the dielectric medium used for detection. MoS 2 monolayers have emerged recently as promising nanostructures for various applications in both the optics and electronics. This paper gives an overview of the optical properties of 2D nanostructures based on this new class of materials. A stronger behavior of the resonance positions in the absorption spectrum exhibits a strong coupling between the LSPR on the gold nanoparticles and the MoS 2 coating film. Numerical simulations display a significant red shift of the plasmonic resonance ( λ max ) and the results show that using a 3.90 nm MoS 2 layer, the plasmon resonance wavelength is increased of 333.7 nm. We also study the performance of the proposed biosensors in terms of sensitivity using multilayers of MoS 2 , and normal incidence to the surface of SiO x /AuNPs/MoS 2 /water and SiO x /MoS 2 /AuNPs/water. We obtain a very high sensitivity of 297.62 nm/RIU corresponding to an increase of 26% compared to the results obtained on SiO x /AuNPs/water, with a location of the electric field on the gold nanoparticles and the covering MoS 2 layer. These characteristics should make these biosensors a preferred choice for detection applications.