Hybrid dielectric-plasmonic nanocomposite arrays for bulk and local refractive index sensing

Abstract

Plasmonics-based biosensors are often limited by material losses in the form of joule heating while all dielectric nanoparticles systems have relatively smaller local electric field enhancements. For efficient sensing, it is desirable to have a system with high sensitivity but with minimal losses. Here, we demonstrate, using numerical simulations, the capability of a hybrid dielectric-plasmonic system for refractive index sensing applications. We show that the optical resonances of such a hybrid system have smaller linewidths and the peak wavelengths are tunable. Bulk as well as local refractive index sensing are demonstrated in this work. Owing to large sensitivities of 300 nm/RIU with a figure of merit (FOM) of 10, the hybrid photonic-plasmonic systems presented here are promising materials for future biosensing applications.