Reversible and Switching Parts of Polarization in PZT Films

A pulsing technique was used for more detailed investigation of the switching process in ferroelectric PZT films. This technique allows for the separation of the switching and reversible parts of the polarization and an estimation of the impact of the different effects in the hysteresis loop such as domain structure, depolarizing field and space charge distribution. It is shown that it is possible to provide nondestructive readout of the information stored as the polarization state by measuring the nonlinearity of the reversible polarization. Theoretical limit for the nondestructive readout signal is 20% of the remanent polarization in the differential regime and 12% in the direct regime. The experimental value of the signal is 10% in the both regimes and does not depend on time or the number of readings.