Excitation of surface plasmon polaritons in gold nano-slab on ion-exchanged waveguide technology
Résumé
Integrated metaphotonic devices had opened new horizons to control light-guiding properties at nanoscale, being particularly interesting plasmonic nanostructures coupled to dielectric waveguides to reduce the inherent light propagation losses in metallic metamaterials. In this contribution, we show the feasibility of using ion-exchanged glass waveguides (IExWg) as a platform for the efficient excitation of surface plasmon polaritons (SPP). These IExWg provide high coupling efficiency and low butt-coupling with conventional dielectric optical waveguides and fibers, overcoming, as well, the hard fabrication tunability of commonly used CMOS-guiding platforms. We present near-field scanning optical microscopy characterization of the propagation characteristics of SPP supported in a gold nano-slab fabricated on top of an IExWg. We found that the SPP can be only be excited with the fundamental TM photonic mode of the waveguide. Thanks to the low propagation loss, low birefringence, and compatibility with optical fibers, glass waveguide technology stands as promising platform for the development of integrated plasmonic devices operating at visible and near infrared wavelengths with potential application in single molecule emission routing or biosensing devices.