  Nanofabrication of photonic components based on dielectric-loaded surface
plasmon-polariton waveguides (DLSPPWs) excited by single nitrogen vacancy (NV)
centers in nanodiamonds is demonstrated. DLSPPW circuits are built around NV
containing nanodiamonds, which are certified to be single-photon emitters,
using electron-beam lithography of hydrogen silsesquioxane (HSQ) resist on
silver-coated silicon substrates. A propagation length of ~20 {\mu}m for the NV
single-photon emission is measured with DLSPPWs. A 5-fold enhancement in the
total decay rate and up to 63% coupling efficiency to the DLSPPW mode is
achieved, indicating significant mode confinement. Finally, we demonstrate
routing of single plasmons with DLSPPW-based directional cou-plers, revealing
the potential of our approach for on-chip realization of quantum-optical
networks.
