Coupled losses in PZT near the morphotropic phase boundary

Abstract
A set of complex dielectric, piezoelectric and elastic constants of undoped PZT ceramics with various Zr/Ti ratios are measured in a temperature range between 4.2 K and the Curie point. In the imaginary parts there exist pronounced loss peaks below 250 K, of which the height and temperature strongly depend on the c/a ratio. For PZT close to the morphotropic phase boundary, but with prevailing rhombohedral symmetry, a second peak above 400 K is observed in all constants.