The evaluation of activation parameters for ferroelectric switching in soft PZT ceramics

The dependence of the coercive field and remanent polarization on temperature was measured for a number of commercial soft PZT ceramics in the temperature range from -175°C to 150°C. It is found that for all ceramics investigated the curves Ec vs. T have a peak in the low temperature region, typically between -100°C and -50°C. As temperature increases in the range from 0°C to 150°C the coercive field decreases nearly linearly. The temperature dependence of the coercive field in this region is explained by means of a micromechanical model based on an Arrhenius equation for the mobilility of domain walls and is used to calculate the activation energy for the domain wall movement in the field of short-range obstacles. Possible effects of microstructure on the activation energy are discussed.