Dielectric stripes on gold as surface plasmon waveguides: Bends and directional couplers

Abstract

Dielectric thin film stripes on a metal surface can be applied as surface plasmon (SP) waveguides. Here, the authors demonstrate experimentally that such structures can be used to build SP waveguide bends and couplers. On one hand, they show that SP transmission through a waveguide bend can be maximized by assuming the trade-off of propagation and bend induced radiation losses. On the other hand, the authors combine two waveguides to form a directional SP coupler.