Optical response of dielectric waveguides loaded with compound plasmonic resonators

In sensing applications of plasmonic nanoantennae, typically, multiple antennae are used (either in a liquid or in periodic arrays), as it is difficult to probe single nanoantenna. We present a numerical study of the optical properties of a dielectric waveguide loaded with a single compound plasmonic nanoantenna and show that a thin nanolayer analyte can be sensed using this structure with a sensitivity of upto 186 nm per RIU. This platform is attractive for performing single-particle sensing, particularly in combination with opto-fluidics.