Structurally dictated anisotropic "designer surface plasmons"

Abstract

The concept of pseudo-plasmonic surfaces at microwave frequencies is extended to include structures with a high degree of surface anisotropy. The experimental sample is fabricated by patterning a metal with a rectangular array of rectangular holes and is found to support structurally dictated surface plasmon-like modes; the anisotropic dispersion of which results from an ellipsoid of limiting frequencies. By exploiting the anisotropy of the unit cell, the family of higher order surface waves associated with the quantization of the electromagnetic fields within the holes is also explored.