Structure, magnetism, and tunable microwave properties of pulsed laser deposition grown barium ferrite/barium strontium titanate bilayer films

Ferrite/ferroelectric films are of interest as they afford dual tunability of the permeability and permittivity using magnetic and electric fields. We have grown bilayered thin films of ferrimagnetic BaFe12O19 (BaM) and ferroelectric Ba0.5Sr0.5TiO3 (BST) on A-oriented polished sapphire substrates using pulsed laser deposition. X-ray thin film analysis (theta-2 theta and azimuthal scans) established highly oriented crystalline films. Magnetic hysteresis loops indicated large magnetic anisotropy between the in-plane and out-of-plane field orientations and the M-H characteristics of BaM were influenced by the presence of the BST layer. Electrical and magnetic tunability studies of the bilayers in the frequency range of 1-65 GHz are also reported. (c) 2007 American Institute of Physics.