Proton-induced achiral structural transition at 180° domain wall in ferroelectrics

Abstract

The influence of proton radiation on the achiral structural transition at 180° domain walls in tetragonal ferroelectric BaTiO3 is theoretically studied in this work. The proton-induced oxygen vacancy in ferroelectrics is predicted using the Monte Carlo Simulations, which increases with the increase of the proton fluence and the energy of the incident proton. A model based on the LGD is developed to investigate the influence of oxygen vacancy which is considered as a defect dipole on the achiral structural transition of Bloch–Néel type of domain wall. Under the proton radiation, the Bloch-type of domain wall shows the character of asymmetric because of the coupling of the polarization and the electric field, while the proton radiation just changes the magnitude of the polarization in the Néel-type of domain wall.