Dynamic response of the dielectric and electro-optic properties of   epitaxial ferroelectric thin films
  An analysis of the dynamic dielectric and electro-optic relaxation response of thin film ferroelectrics is presented. The analysis is based upon the relaxation of ferroelectric domains with a continuous distribution of sizes given by percolation theory. The resulting temporal response is described by the expression (t^-m) exp(-(t/tau)^beta). The analysis was applied to KNbO3 thin films. Measurements of the polarization, birefringence and dielectric transients show qualitative agreement with the model over 11 orders of magnitude in time. 
B. H. Hoerman, B. M. Nichols and B. W. Wessels (Department of   Materials Science and Engineering, Northwestern University, ...