Phase-field modeling and electronic structural analysis of flexoelectric effect at 180° domain walls in ferroelectric PbTiO3

Abstract

Flexoelectric effect is the coupling between strain, polarization and their gradients, which are prominent at the nanoscale. Although this effect is important to understand nanostructures, such as domain walls in ferroelectrics, its electronic mechanism is not clear. In this work, we combined phase-field simulations and first-principles calculations to study the 180° domain walls in tetragonal ferroelectric PbTiO3, and found that the ultimate source of Néel components is the gradient of the square of spontaneous polarizations. Electronic structural analysis reveals that there is a redistribution of electronic charge density and potential around domain walls, which produces the electric field and Néel components. This work thus sheds light on the electronic mechanism of the flexoelectric effect around 180° domain walls in tetragonal ferroelectrics.

References in corpus (10)

• Strain gradient induced polarization in SrTiO3 single crystals
• Ab initio study of ferroelectric domain walls in PbTiO3
• Giant Flexoelectric Effect in Ferroelectric Epitaxial Thin Films
• Conduction at domain walls in insulating Pb(Zr${}_{0.2}$Ti${}_{0.8}$)O${}_3$ thin films
• Atomistic determination of flexoelectric properties of crystalline dielectrics
• Breaking of macroscopic centric symmetry in paraelectric phases of ferroelectric materials and implications for flexoelectricity
• Ferroelectricity at ferroelectric domain walls
• Domain wall conduction in multiaxial ferroelectrics
• Bichiral structure of feroelectric domain wall driven by flexoelectricity
• Bloch-type Domain Walls in Rhombohedral BaTiO3

Cited by in corpus (1)

• Ab Initio bulk free energy surface of proper ferroelectrics