Surface plasmon reflection at edges and resonance effects in metal bars

The field patterns of surface plasmons excited in ATR configuration on continuous metal films, at edges of metal layers and on single metal wires have been simulated numerically using finite-difference time-domain calculations. We find reflection of surface plasmons at steep edges, but not at very smooth ones. For single metal wires, we observe a dependence of the field pattern on the width of the wires. In addition, a metallic valley structure designed for confining surface plasmons is discussed.