Calculation of frequency-dependent coercive field based on the investigation of intrinsic switching kinetics of strained Pb(Zr0.2Ti0.8)O3 thin films

We report a method to predict the frequency dependence of coercive fields in ferroelectric films. The deduction of this method as well as the analysis are based on investigations of intrinsic switching kinetics of high-quality, single-crystal-like, epitaxial Pb(Zr0.2Ti0.8)O-3 thin films with extended defect-free structures. The newly suggested relationship, i.e. an exponential decrease in frequency with the reciprocal of the coercive field, differs from the empirical power-law relationship. The proposed equation relates the coercive field (E-c) measured using ferroelectric hysteresis loops to the activation fields determined from pulse width switching measurements, which provides a way to understand the behaviour of Ec as a function of frequency from the switching kinetics point of view.