Unexpected dielectric response in lead zirconate titanate ceramics: The role of ferroelectric domain wall pinning effects

Temperature dependent dielectric response has been measured in Pb(Zr1−xTix)O3 ceramics. Samples of different compositions (x=0.40, 0.47, and 0.60), pure and doped with Nb-or Fe, were studied at temperatures between 15 and 700K and in the frequency range from 100Hzto1MHz. Unexpected dielectric behavior has been found around room temperature. Anomalous temperature dependent permittivity is observed in pure and Fe-doped samples but not in Nb-doped samples. The anomaly appears related to the presence of oxygen vacancies but not on the sample crystallographic phase. The authors suggest that the anomaly may be a manifestation of the domain wall pinning effect.