Electromagnetic energy transport along arrays of closely spaced metal rods as an analogue to plasmonic devices

Abstract

The transport of electromagnetic energy along structures consisting of arrays of closely spaced metal rods $(\mathrm{spacing}\text{=0.2\hspace{0.05em}}\mathrm{cm})$ was investigated in the microwave regime at $\text{8.0\hspace{0.05em}}\mathrm{GHz}\text{\hspace{0.05em}(λ=3.7\hspace{0.05em}}\mathrm{cm}\mathrm{).}$ The dispersion relation shows that information transport occurs at a group velocity of 0.6c. The electromagnetic energy is highly confined to the arrays (90% within a distance of 0.05λ from the array). The propagation loss in a straight array is 3 dB/8 cm. Routing of energy around 90° corners is possible with a power loss of 3–4 dB. Analogies to plasmon wires consisting of arrays of nm-size metal clusters are discussed.