The ferroelectric polarization loop of an epitaxial BiFeO3 film on a piezoelectric substrate has been investigated as a function of continuously and reversibly varied biaxial strain of ε=0.36%-0.51%. Over this range, the ferroelectric coercive field (EC) at 80 K increases reversibly by 36% with the increasing tensile strain. In contrast, phase-field simulations predict the opposite trend of d EC/dε<0. Therefore, we attribute the observed EC (ε) dependence to the strain dependence of domain dynamics, which are not included in thermodynamic models. The strain dependence of the remanent polarization agrees with previous results.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)