  Transport properties of a single plasmon interacting with two quantum dots
(QDs) system coupled to one-dimensional surface plasmonic waveguide are
investigated theoretically via the real-space approach. We mainly focus on the
coupling effects of the two QDs on the transmission properties of a single
incident plasmon. We demonstrated that switching of a single plasmon can be
achieved by controlling the interparticle distance, the interparticle coupling
strength, and the QD-waveguide coupling strength, as well as spectral detuning.
We also showed that the coupling between the continuum excitations and the
discrete excitations results in the Fano-type transmission spectrum. The
transport properties of a single plasmon interacting with such a two direct
coupled QDs system could find the applications in the design of plasmonic
nanodevices, such as single photon switching and nanomirrors, and in quantum
information processing.
