Study of a residual ferroelectric contribution in antiferroelectric lead-zirconate thin films

In this study, First-Order Reversal Curves (FORC) measurements and impedance spectroscopy coupled to hyperbolic law analysis have been used in order to characterize lead zirconate antiferroelectric thin films elaborated by a sol-gel process. The presence of a weak residual ferroelectric behavior has been shown even if this contribution is not clearly visible on the polarization-electric field loops. Moreover, FORC measurements indicate that the weak ferroelectric phase switch only when the antiferroelectric phase state of the cell is modified. On the other hand, impedance spectroscopy reveals a fairly good distribution of small residual ferroelectric clusters in the material as no coalescence of ferroelectric domains has been observed at low fields. This study aims to show that FORC distribution measurements and impedance spectroscopy coupled to the hyperbolic law analysis are very sensitive and complementary methods for the understanding of the polarization switching dynamics in antiferroelectric materials.