Vortex switching in epitaxial nanodot under uniform electric field: The effect of misfit strain

Abstract

Epitaxial strain plays an extraordinary role in the formation, evolution, and phase transition of topological domain structures in nanoscale ferroelectrics. Unfortunately, how vortex switching reacts to misfit strain in epitaxial nanodots remains unclear. Based on phase-field simulations, the reversal of vortex chirality in an epitaxial triangular nanodot induced by a uniform electric field applied along various directions is systematically investigated as a function of misfit strain. The results indicate that three basic types of vortex switching exist in an epitaxial triangular nanodot: type I under compressive strain, type II under tensile strain, and a narrow transition type with the characteristics of types I and II. The results show that misfit strain plays a crucial role in determining the type of vortex switching. This work, thus, clarifies the role of misfit strain and could be conducive to facilitating the mechanical manipulation of ferroelectric nanoelectronic devices.