Over the past 25-30 years there has been great interest in periodic composite structures consisting of magneto-dielectric constituents as well as metallic wires, flakes, etc. The motivation for these studies has been to determine a particular configuration which may lead to electrical and/or magnetic properties which naturally cannot be obtained from single constituents. One configuration which appeared to be very promising consisted of periodic distribution of wires and rings in either one or two dimensions. In the literature these composite structures were referred to as left handed media. It was shown that the periodic wires structure led to negative effective permittivity. Furthermore, split ring resonators (SRR) gave rise to a negative permeability. However, when these two structures were combined, such that the electromagnetic electric field, e, was parallel to the wire direction and the electromagnetic magnetic field, h, was perpendicular to the SRR elements or the ring, there resulted an effective negative index, n. Potential applications to radar and microwave technologies have been explored. The purpose of this paper is to do away with the SRR metamaterial structure by introducing ferrites to replace the SRRs. The negative index may be obtained by having both wires and ferrites in a meta-material ferrite structure. Such a structure is vastly more practical in shape and size than the wire-SRR construct.
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