High frequency properties of high voltage barium titanate-ferrite multiferroic metamaterial composites

Permittivity and permeability parameters of dielectric composites made of ferrite particles coated in a barium titanate (BaTiO
₃
) layer were analyzed and compared against composites of ferrite powders without a dielectric layer. A hydrothermal synthesis process combined barium hydroxide (Ba(OH)
₂
) and titanium dioxide (TiO
₂
) to form the coating of barium titanate around a ferrite core. These barium titanate ferrite composites particles are then combined with a unique binder to form a metamaterial. Discs of the metamaterial are characterized with an Agilent coaxial airline and dielectric measurement software to determine the permittivity and permeability responses within a frequency range of 200 MHz to 4 GHz. By comparing these results to previous work on ferrite composites, the merit of insulating the magnetic particles with a dielectric layer is examined.