Subwavelength coherent control and coupling of light in plasmonic nanoresonators on dielectric waveguides

We report results on the possibility of subwavelength coherent control of light in coupled plasmonic nanoresonators on dielectric waveguides. Our calculations show that subwavelength regions of the plasmonic structure, spatially separated by a few nanometers, can be individually addressed by controlling the relative phase of the injected fields. We also show the complementary possibility to efficiently inject a guided mode into a planar dielectric waveguide by collecting the radiation emitted by wire-like and/or point-like sources, placed into the resonators. For example, this configuration provides a useful and powerful tool to control the emission of the localized sources such as stripes of fluorescent molecules or quantum dots placed in the gaps between the plasmonic structures. Possible applications of the considered study include plasmonic logic gates, integrated sensors for single-molecule fluorescence, and ready-to-use devices based on plasmonic single-photon sources. © 2013 Optical Society of America.