Polarization Reversal in Relaxor PZN-PT Single Crystals

The polarization reversal under application of bipolar ac field and dielectric properties were investigated in wide temperature range in PZN-xPT (x = 4.5 and 8%) single crystals. The observed temperature dependences of the dielectric permittivity during heating after field-cooling and zero-field-cooling were discussed on the basis of several phase transformations and existing of the heterophase structures in given temperature range. The “doubling” of the hysteresis loops reveled during heating in limited temperature range was explained using quasi-static Preisach approach taking into account the key role of inhomogeneous depolarization field Edep.