The dielectric and piezoelectric properties of an epitaxial $\mathrm{PbZ}{\mathrm{r}}_{0.8}\mathrm{T}{\mathrm{i}}_{0.2}{\mathrm{O}}_3/\mathrm{PbZ}{\mathrm{r}}_{0.6}\mathrm{T}{\mathrm{i}}_{0.4}{\mathrm{O}}_3$ ferroelectric bilayer film were studied. Time-resolved synchrotron x-ray microdiffraction provided access to layer-specific structural information during electric-field-induced changes. The observed dielectric and electromechanical responses are consistent with a weak electrostatic polarization coupling and can be described using a thermodynamic model of epitaxial ferroelectric bilayers. The weak electrostatic coupling between ferroelectric layers can enable unusual tail-to-tail and head-to-head polarization configurations. X-ray measurements of the piezoelectric response of the ferroelectric bilayer at a microsecond time scale confirmed a possible tail-to-tail polarization domain configuration.

• Received 21 November 2013
• Revised 20 January 2015

DOI:https://doi.org/10.1103/PhysRevB.91.104106