Larger polarization and weak ferromagnetism in quenched BiFeO3 ceramics with a distorted rhombohedral crystal structure -: art. no. 262907

Single-phase insulating BiFeO3 ceramics have been synthesized by a simple but effective method that conventional solid state reaction is followed immediately by quenching processing. At room temperature, the ceramics show a metastable, distorted rhombohedral phase and the refined structure parameters are presented based on x-ray diffraction. It is revealed that the formations of Fe2+ and oxygen deficiency are greatly suppressed by the quenching processing. A well-saturated ferroelectric hysteresis loop with a large remnant polarization (2P(r) = 23.5 mu C/cm(2)) is observed with an applied field of 155 kV/cm. Temperature-dependent magnetic property is investigated and weak ferromagnetism with a remnant magnetization of 4 x 10(-6) mu(B)/Fe at 10 K is established. These results may have implications for further studies on multiferroics. (c) 2005 American Institute of Physics.