First order reversal curves diagrams applied for the ferroelectric systems

First Order Reversal Curve (FORC) diagrams are proposed for the description of switching properties in ferroelectrics. Non-symmetric P(E) hysteresis loops of Pb(Zr,Ti)O-3 ferroelectric films, recorded between various reversal fields and the saturation field were used in order to calculate the FORC distributions. A clear separation of the reversible and irreversible contributions to the ferroelectric polarization was obtained on these diagrams. The FORC diagrams are sensitive to various parameters, such as frequency, fatigue state and crystallite orientation in the sample. The FORC susceptibilities show the critical regimes for the linear/nonlinear behaviour of the ferroelectric material and their characteristics.