Long-range Plasmonic Waveguides with Polymer Claddings

Metallic surfaces can support surface-bound guided optical modes through interaction of the optical field with the electron density oscillations. Propagation of these surface waves, also called surface plasmon polaritons, is a very lossy process, due to mode overlap and heat dissipation within the metal. In principle thin metal stripes can support longer propagation lengths, however in the fabrication process it is imperative to balance the refractive index of the claddings. In this paper different techniques for fabricating long-range plasmonic waveguides are presented, together with results of optical characterization of the fabricated samples. The waveguides are fabricated using gold and the claddings are chosen to be SU-8 and PDMS polymers.