Polarization dynamics in a ferroelectric relaxor excited by short pulses

Polarization dynamics in a relaxor ferroelectric is investigated by exciting samples, set at different temperatures, with short high voltage (approximate to1 kV) rectangular pulses (approximate to200 ns) and then by measuring the charge carried to the sample, i.e., the polarization. Further important information is extracted from the trailing edge of the charge signals, which detect the relaxation of the polarization. Polarization dynamics of zero-field-cooled samples show a logarithmic increase during the voltage pulse plateau and a logarithmic decay after the pulse. The slopes depend on the field amplitude and temperature. The model of reorientable noninteracting polar clusters adequately describes the experimental behaviors.