The evolution of anti-vortex like domain under electric field in polycrystalline ferroelectric

Domain wall (DW) plays an important role in the domain evolution. The anti-vortex could be a special domain structure of the mixed DWs, i.e. the Ising wall and the Mixed Ising-Neel wall. The anti-vortex domain in polycrystalline ferroelectric has been investigated by a modified first-principles-based atomistic method incorporating the anisotropic shell model. Results show that the nucleation and the disappearance of the anti-vortex happen at grain boundaries (GBs) under sinusoidal electric fields loading. As the anti-vortex motion by the electric field, it is a perfect view point for the domain evolutions. It has been found that the anti-vortex core can't pass through the GBs because of the size and disorder field. This phenomenon indicates that anti-vortex is only been obtained in grains at polycrystalline ferroelectric, and the electric field range must between −6.3 and 6.3 × 108 V/m.