Magnetic hysteresis of cerium doped bismuth ferrite thin films

The influence of Cerium doping on the structural and magnetic properties of BiFeO3 thin films have been investigated. Rid:veld refinement of X-ray diffraction data and successive de-convolution of Raman scattering spectra of Bi1-xCexFeO3 (BCFO) thin films with x=0-0.20 reflect the single phase rhombohedral (R3c) formation for x < 0.08, whereas concentration-driven gradual structural phase transition from rhombohedral (R3c) to partial tetragonal (P4mm) phase follows for x >= 0.08. All low wavenumber Raman modes (< 300 cm(-1)) showed a noticeable shift towards higher wavenumber with increase in doping concentration, except Raman E-1 mode (71 cm 1), shows a minor shift. Sudden evolution of Raman mode at 668 cm(-1), manifested as A(1)-tetragonal mode, accompanied by the shift to higher wavenumber with increase in doping concentration (x) affirm partial structural phase transition. Anomalous wasp waist shaped (M-I-I) hysteresis curves with improved saturation magnetization (M-s) for BCFO thin films is attributed to antiferromagnetic interaction/hybridization between Ce 4f and Fe 3d electronic states. The contribution of both hard and soft phase to the total coercivity is calculated. Polycrystalline Bi0.88Ce0.12FeO3 thin film found to exhibit better magnetic properties with M-s =15.9 emu/g without any impure phase. (C) 2014 Elsevier B.V. All rights reserved