Near-infrared metamaterials with dual-band negative-index characteristics.

Dual-band negative-index metamaterial designs in the near-infrared frequency range are presented and their performance is analyzed using a full-wave numerical electromagnetic scattering method. Negative effective permittivity is provided by a thin layer of metallic film. Negative effective permeabilities are supplied in two distinct frequency bands by magnetic resonators of different dimensions. Initial two-dimensional infinite structures are then extended to doubly-periodic designs and the corresponding dual-band characteristics are presented.