Optical Properties of Single-Mode Side-Polished Fiber Covered with Multilayer Planar Waveguide Including Metal Films

The fiber-to-planar waveguide (PWG) couplers with two vertically separated metals films have been proposed, and theoretical and experimental investigation of the behavior of the coupler have been presented. Based on the normal-mode theory, the influence of the structural parameters on the characteristics of the device was analyzed and explained. The measured behavior of the device was in good agreement with theoretical predictions. Depending on the structural configuration, the device behaved as either a narrower filter or a polarizer. The possibility of its application as an active component has also been examined.