  A novel type of a plasmonic waveguide has been proposed featuring an "open"
design that is easy to manufacture, simple to excite and that offers a
convenient access to a plasmonic mode. Optical properties of photonic bandgap
(PBG) plasmonic waveguides are investigated experimentally by leakage radiation
microscopy and numerically using the finite element method confirming photonic
bandgap guidance in a broad spectral range. Propagation and localization
characteristics of a PBG plasmonic waveguide have been discussed as a function
of the wavelength of operation, waveguide core size and the number of ridges in
the periodic reflector for fundamental and higher order plasmonic modes of the
waveguide.
