Numeric Simulations of a Novel Wideband Electromagnetic Band Gap Metamaterial Utilizing Oriented Cobalt-Substituted Z-Type Barium Hexaferrites

The material parameters of an electromagnetic bandgap (EBG) metamaterial consisting of metallic Sievenpiper structures prepared upon a Co₂Z hexaferrite substrate having μr = 12 to 14 and εr = 10 to 12 are reported. A bandwidth of 50%-75% of L-band was realized in simulation. The synthesis of the Co₂Z hexaferrite material with optimized properties was achieved via a modified aqueous coprecipitation method with yields of up to 25 g/L. Magnetically oriented Co₂Z substrates were demonstrated to exhibit a zero-field ferromagnetic resonance frequency of ~1.1 GHz that enabled device application from ultrahigh frequency (UHF) through L-band frequencies. EBG metamaterials designed and simulated on an oriented Co₂Z hexaferrite substrate were compared to standard dielectric EBG designs. Results indicate that standard dielectric EBG designs, which operate over a 50% bandwidth and profile height of ~λo/10, are replaceable with an equivalent bandwidth Co₂Z EBG metamaterial designed to a height of ~λo/95. The applications of the proposed metamaterial toward ultralow profile antenna designs at UHF through L-band are discussed.