Abstract
The composition dependence of dielectric and piezoelectric nonlinearities were characterized in epitaxially grown (0.3)Pb(Ni0.33Nb 0.67)O3-(0.7)Pb(ZrxTi1-x)O 3 thin films deposited on SrTiO3. Tetragonal, morphotropic phase boundary (MPB) and rhombohedral films were prepared by changing the Zr/Ti ratio. The relative dielectric permittivity εr and the converse piezoelectric coefficient d33,f were found to follow the Rayleigh law. The local piezoelectric nonlinearity map showed the formation of micron-sized clusters of higher nonlinear activity for the MPB and rhombohedral compositions. The ratios of the irreversible to the reversible Rayleigh constants αε/εinit and the spatially averaged αd/d33,init ratio were larger for the rhombohedral and MPB compositions compared to the tetragonal composition. The larger dielectric and piezoelectric nonlinearities observed for the rhombohedral sample are interpreted in terms of a higher domain wall mobility due to a smaller ferroelectric distortion and superior crystal quality.
| Original language | English |
|---|---|
| Article number | 044109 |
| Journal | Journal of Applied Physics |
| Volume | 110 |
| Issue number | 4 |
| DOIs | |
| State | Published - Aug 15 2011 |
Funding
Support for this work was provided in part by the National Security Science and Engineering Faculty Fellowship and by CNMS user proposal CNMS2010-090 (F.G. and S.T.-M.). A portion of this research was conducted at the Center for Nanophase Materials Sciences, which is sponsored at Oak Ridge National Laboratory by the Office of Basic Energy Sciences, U.S. DOE. Thanks to Clive Randall for the insightful discussions and for sharing his knowledge of ferroelectric microstructure-property relations and to Josh Maier for the TEM sample preparation.