Nonresonant structured material with extreme effective parameters

We demonstrate that a metamaterial formed by crossed metallic wires is characterized by an anomalously high index of refraction. Such property does not rely on a resonant response of the inclusions, but rather is a consequence of the ultrahigh density of the wires and of the strong electromagnetic interaction between crossed wires. It is shown that the bandwidth of such phenomenon can be quite large, and that it is mildly affected by metallic loss in the far-infrared domain. Prospective applications in the miniaturization of waveguides and other devices are discussed.