Room temperature ferroelectric, ferromagnetic and magnetoelectric properties of Ba-doped BiFeO3 thin films

Abstract

Ba-doped multiferroic BiFeO3thin films were successfully prepared on Pt/TiO2/SiO2/Si(1 0 0) substrates by pulsed laser deposition. X-ray diffraction showed that the Bi0.75Ba 0.25FeO3thin film was single phase with (1 0 1) preferential polycrystalline orientation. Both ferroelectricity and ferromagnetism of these films were observed at room temperature by P-E and M-H loop measurements, respectively. The magnetoelectric coupling effect was demonstrated by measuring the dielectric constant in a varying magnetic field. The dielectric constants measured at 10 kHz increased with an increase in the applied magnetic field, giving a coupling coefficient (εr (H) - εr (0))/εr (0) of 1.1% at H ≤ 8 kOe at room temperature, which shows potential application. © 2007 IOP Publishing Ltd.