Characterization of Multiferroic Thin Films Generated with Molecular Beam Epitaxy

Magnetoelectric multiferroic thin films exhibit coupled ferromagnetism and ferroelectricity. Interest in these multiferroics stems from their potential applications in spin-based computing and novel information storage methods. Through characterization with x-ray diffraction (XRD), atomic force microscopy (AFM), and vibrating sample magnetometry (VSM), the growth of multiferroic films with molecular beam epitaxy (MBE) was optimized. Both strain-coupled FexGa1-x composites and rare earth ferrite superlattices were studied. Additionally, this study searched for compatible bottom electrodes that facilitate the measurement of the ferroelectric properties of the films. Because the electrodes are necessarily located between the substrate and the film, all three must have compatible crystal lattice parameters in order to grow successfully with MBE. Characterization of the electrodes with XRD omega rocking curves and AFM revealed that PIN-PMN-PT produced slightly better iridium electrodes and FexGa1-x films than PMN-PT.