For understanding the reaction of the domain structure and crystallographic structure of ferroelectric lead zirconate titanate, $\mathrm{Pb}\left[{\mathrm{Zr}}_{1-x}{\mathrm{Ti}}_x\right]{\mathrm{O}}_3$, to an applied electric field and its high piezoelectric properties for compositions in the vicinity of the morphotropic phase boundary (MPB), investigations of structural changes under in situ conditions are of great importance. As we have shown in recent studies [L. A. Schmitt et al., J. Appl. Phys. 101, 074107 (2007); K. A. Schönau et al., Phys. Rev. B 75, 184117 (2007)] the domain structure miniaturizes at the MPB. This nanodomain structure and its stability field are crucial for the character of the poling behavior of the material. In situ electric field synchrotron powder diffraction studies across the entire compositional range of the MPB show changes in phase fractions, domain structure, and phase transitions under electric field dependent on the nanodomain content. For a certain range of tetragonal $c∕a-$ratio the nanodomains are stabilized, straining tetragonal microdomains under electric field, while with further decreasing $c∕a-$ratio at higher Zr contents they are transformed into a structure associable with rhombohedral microdomains.

• Received 15 May 2007

DOI:https://doi.org/10.1103/PhysRevB.76.144112