Multiferroic properties of (La_0.2Bi_0.8FeO₃)_0.8 -(NiFe₂O₄)_0.2 films grown by pulse laser deposition

(La_0.2Bi_0.8FeO₃)_0.8 -(NiFe₂O₄)_0.2 (LBFO-NFO) thin films were grown on (100) SrTiO₃ substrates by pulse laser deposition. X-ray diffraction and Field Emission Scanning Electronic Microgrape studies confirm that the phases of LBFO and NFO in the films grow along the direction of (100) and the particle sizes of the two phases are about 100-150 nm, respectively. The ferroelectric and ferromagnetic hysteresis of the films measured with a standardized ferroelectric test system (RT-66A, Radiant technologies) and vibrating sample magnetometer (VSM) show that the saturation polarization and magnetization are 7.6 μC/cm² and 4.12 × 10⁴ A/m respectively, which indicates that LBFO-NFO films possess multiferroic properties obviously. By controlling the growth condition of the films, the leakage current of LBFO-NFO films can be decreased. Accordingly, the ferroelectric and ferromagnetic properties can be enhanced greatly.