Finite-size effects in BaTiO3 nanowires

Abstract

The size dependence of the ferroelectric properties of BaTiO 3 nanowires is studied from first principles. We show that the ferroelectric distortion along the wire axis disappears below a critical diameter of about 1.2nm . This disappearance is related to a global contraction of the unit cell resulting from low atomic coordinations at the wiresurface. It is shown that a ferroelectric distortion can be recovered under appropriate tensile strain conditions.