Theoretical and experimental investigations of polarization switching in ferroelectric materials

The polarization switching process is certainly the most important feature of ferroelectric materials from fundamental as well as practical points of view. In this paper, a one-dimensional lattice model is presented in order to describe the polarization switching process in ferroelectric materials, incorporating the contribution of both dipolar defects and depolarizing fields to the domain reorientation. The influence of the interaction strength between switchable dipoles and dipolar defects, the medium viscosity, the depolarizing fields, and the frequency of the external electric field on the polarization switching were simulated. It was found that the degree of interaction between domains and dipolar defects has a strong influence on the coercive field, polarization, and backswitching behavior. Through an adequate analysis of the variables in the model it was also possible to describe the evolution of the polarization switching with the number of electric field cycles, which is commonly observed in the fatigue or depinning process. Comparison between simulated and experimental results revealed a remarkable concordance.