Lead lanthanum zirconate titanate (PLZT x/59/41) ceramics with x from 0 to 6.5 mol.% are synthesized by the traditional solid-state reaction method. The temperature dependences of dielectric and resonant responses are used to characterize the depolarization processes of poled samples. It is found that the temperature of anti-resonance frequency minima (Tmin-a) accords completely with dielectric loss peak temperature (T-loss). The Tloss instead of anomalous dielectric peak temperature (T*(d)) can be regarded as depolarization temperature (T-d). The T*(d) deviated from the T-loss suggests that the depolarization process in all the samples includes two stages: domain decoupling and polarization disorientation. With La content increasing, the T-loss decreases and the temperature difference Delta T between T-loss and dielectric peak temperature (T-m) increases nearly linearly. Since all studied samples have similar depolarization and freezing processes and the 0 mol. % La sample behaves like a normal ferroelectric, here we suggest that there may be no essential difference in depolarization process between relaxor and normal ferroelectrics. Published by AIP Publishing.
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