Enhancing the generation of surface plasmons with optical nanoantennas
Abstract
An integrated source of surface plasmons with a large efficiency would represent an important building block for nanophotonics. Unfortunately, a light emitter located far from a metal surface is only weakly coupled to surface plasmons while an emitter positioned close to a metal surface is quenched. We theoretically show an enhancement of the surface plasmon generation by more than three orders of magnitude when the emission is assisted by a carefully designed nanopatch antenna. Such huge enhancements result from the use of hybrid modes that have both a large Purcell factor and a good efficiency for radiating surface plasmons.