The effect of flexoelectricity on domain switching in the vicinity of a crack in ferroelectrics

Ferroelectrics are widely used in the manufacture of transducers, actuators, and memory devices, due to their attractive electromechanical properties. However, the reliability and failure of devices is greatly dependent on their brittleness. In view of the fact that both the polarization distribution and elastic field are at nanoscale and vary greatly in the vicinity of the crack tip, flexoelectricity is expected to strongly affect the domain configuration. In this work, Ginzburg-Landau (TDGL) theory and the phase field method (PFM) are employed to analyze the influence of flexoelectric effect on the domain switching process in the vicinity of the crack tip of ferroelectric materials. The results obtained show that, the domain configuration would become asymmetric with increasing flexoelectric coefficients, and the flexoelectric effect has a larger influence on the polarization field than on the elastic field in the vicinity of the crack tip of ferroelectric materials.