Phase-field simulations of vortex chirality manipulation in ferroelectric thin films

Abstract

The ferroelectric chiral vortex domains are highly desirable for the application of data storage devices with low-energy consumption and high-density integration. However, the controllable switching of vortex chirality remains a challenge in the current ferroelectric community. Utilizing phase-field simulations, we investigate the vortex domain evolution and chirality formation in BiFeO3 thin films. By applying local surface charge or electric field, we demonstrate that the vorticity and the polarity can be manipulated by the initial bi-domain arrangement and the external field with different directions, respectively. By exchanging the domain arrangements, the opposite chirality can be obtained. Importantly, the topological vortex domain is retained after removing the external field. The vortex chirality can be switched reversibly with high reproducibility, which is beneficial to fatigue tolerance of the material in the operation. These results provide theoretical guidance for manipulating the vortex chirality in ferroelectric films.