Magnetoelectric ceramic composites with double-resonant permittivity and permeability in GHz range: A route towards isotropic metamaterials

The magnetoelectric ceramic composite formed by Pb-0.988(Zr0.52Ti0.48)(0.976)Nb0.024O3 (PZTN) and CoFe2O4 (CF) was prepared in situ by citrate-nitrate combustion on the PZTN powder template. The electromagnetic properties showing double negative resonance with negative values of dielectric permittivity epsilon(r) and magnetic permeability mu(r), in a close frequency range of 2 x 10(8) Hz to 2.6 x 10(9) Hz, are reported. In addition, the condition of impedance matching with free space epsilon(r) = mu(r) is accomplished at the frequency f = 280 MHz in these ceramic composites. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.