Surface plasmon dielectric waveguides
  We demonstrate that surface plasmon polaritons can be guided by nanometer scale dielectric waveguides. In a test experiment plasmons were coupled to a curved 3 micrometer radius dielectric stripe, which was 200 nm wide and 138 nm thick using a parabolic surface coupler. This experiment demonstrates that using surface plasmon polaritons the scale of optoelectronic devices based on dielectric waveguides can be shrunk by at least an order of magnitude. 
Igor I. Smolyaninov, Yu-Ju Hung, and Christopher C. Davis