Switching kinetics in epitaxial BiFeO3 thin films

The switching kinetics in epitaxial (001)-, (110)-, and (111)-oriented BiFeO3 thin films were investigated as a function of applied field and time. It was found that the ferroelectric switching behavior obeys the Kolmogorov-Avrami-Ishibashi theory only in the high field range. The detailed behavior depends on the film orientation. A comparison with standard systems, such as epitaxial Pb (Zr0.2 Ti0.8) O3 films, reveals some similarities as well as some differences. For instance, the presence of 109° and 71° ferroelastic domain walls might be ruled out as the source of the decrease in switched polarization at low applied fields, in contrast to what is the case for a/c domain walls in tetragonal Pb (Zr 0.2 Ti0.8) O3. © 2010 American Institute of Physics.