ABSTRACT
Metamaterials or their two-dimensional analogues, metasurfaces, are generally made of basic elements containing metallic parts. The latter are generally very thin and conductive, which makes a theoretical analysis rather subtle: One cannot just let the thickness of the elements tend to zero, because the metamaterial would simply disappear in the end. This chapter investigates the problem of the effective properties of a wire medium. A bidimensional metamaterial made of a biperiodic arrangement of infinitely long and very conducting wires is considered. The homogeneous model is tested by comparing it with three- dimensional full vector simulations of the structure. The reflection, transmission, and absorption coefficients and the current distribution of the homogeneous problem are compared with those of the original bed-of-nails metamaterial. The bed-of-nails structure is a medium exhibiting high absorption with low reflection. It requires a very low filling fraction of conducting material but exhibits near-perfect absorption over a wide range of angles of incidence, for sufficiently large thicknesses.
