Electromechanical resonance in ferrite-piezoelectric nanopillars, nanowires, nanobilayers, and magnetoelectric interactions

A model is presented for magnetoelectric (ME) effects in the region of electromechanical resonance (EMR) for ferrite-piezoelectric nanobilayers, nanopillars, and nanowires on a substrate or a template. Influence of the lattice mismatch on the material parameters and ME interactions has been taken into account using the classical Landau-Ginsburg-Devonshire phenomenological thermodynamic theory. The clamping effect of the substrate for nanobilayers and nanopillars or template for nanowires have been considered in determining the ME voltage coefficient. The model is applied to nickel ferrite-lead zirconate titanate nanostructures on strontium titanate substrate or template. It is shown that the ME coupling strength decreases with increasing substrate or template volume fraction. For increasing thickness of substrate for a bilayer or the template radius for a nanowire (i) the ME coefficient drops exponentially and (ii) EMR frequency increases. For nanopillars on a substrate, a fine structure is predicted in the ME voltage versus frequency profile. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3359717]