A negative index of refraction metamaterial based on a wire array embedded in ferrite

摘要

A metamaterial exhibiting a negative index of refraction can be fabricated from an array of conducting wires cladded with non-magnetic dielectric and embedded in a magnetic host medium. The wires are responsible for the ε < 0 property and the magnetic medium for the μ < 0 property. A near exact calculation of the electromagnetic response of this metamaterial indicated that the bandwidth over which n < 0 depends primarily on the magnetization of the magnetic host and on the radius of the wire, the outer radius of the cladding, and the lattice constant of the wire array. For readily available materials the dissipation within the medium is mainly due to Ohmic losses within the wire and not magnetic dissipation within the magnetic host. The losses can be minimized by choosing a high conductivity metal for the wire and by having the radius of the wire and outer radius of the cladding as large as practical consistent with maintaining ε < 0.