Stochastic model of dispersive multi-step polarization switching in ferroelectrics due to spatial electric field distribution

A stochastic model for polarization switching in tetragonal ferroelectric ceramics is introduced, which includes sequential 90°- and parallel180°-switching processes and accounts for the dispersion of characteristic switching times due to a nonuniform spatial distribution of theapplied field. It presents merging of the recent multistep stochastic mechanism with the earlier nucleation limited switching and inhomoge-neous field mechanism models. The model provides a much better description of simultaneous polarization and strain responses over a widetime window and a deeper insight into the microscopic switching mechanisms, as is exemplarily shown by comparison with measurementson lead zirconate titanate