Manipulating Surface Plasmons Propagation Using Ultra-Compact and Non-Dielectric Designs

The work presents a method capable of manipulating and controlling the propagation of surface plasmons using plasmonic structures composed of only metals. In our approach, we make use of a semi-infinite silver block inserted into another semi-infinite medium made of rhodium. To design the structures here studied, the effective medium concept is exploited by considering that surface plasmons propagate at the air-metal interface with an effective refractive index. Here we design, demonstrate and evaluate a plano-convex lens with the ability to focus the incident surface plasmons onto a single focal spot.