Room-temperature magnetoelectric coupling in single-phase BaTiO 3-BiFeO3 system

Abstract

In this paper, single-phase multiferroic ceramics of (1 - x) BaTiO 3 - x BiFeO3 (BT - x BFO) were synthesized by solid-solution method in the wide range of material composition (x = 0.025 - 1.0). The changes in crystal structure were confirmed via X-ray diffractions (XRD) and atomic pair distribution functions (PDFs). The room-temperature ME coupling was found to exhibit significant magnitude in the narrow composition window (x = 0.71 - 0.8) where the average crystal structure was found to be rhombohedral. Especially, the BT - 0.725 BFO ceramics containing local monoclinic distortions within rhombohedral phase were found to exhibit high room-temperature ME coefficient (αME) of 0.87 mV/cm·Oe with high piezoelectric properties (g33 = 18.5 × 10 mV m N -1 and d33 = 124 pC N-1). We believe that the high room-temperature ME coupling in single-phase lead-free BT-BFO ceramics provides a possibility of developing electrically or magnetically tunable thin-film devices. © 2013 American Institute of Physics.