A composite material exhibiting at least one of a negative effective permittivity and a negative effective permeability for incident radiation at an operating wavelength is described. The composite material comprises a dielectric layer generally parallel to a dielectric layer plane, and further comprises a first plurality of nanowire pairs disposed in the dielectric layer. Each of the first plurality of nanowire pairs comprises substantially parallel conductive nanowires of short length and separation relative to the operating wavelength. Each of the first plurality of nanowire pairs is substantially coplanar with a first plane substantially parallel to the dielectric layer plane.