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Finite-size effects in BaTiO3 nanowires

Gregory Geneste·Eric Bousquet·Javier Junquera·Philippe Ghosez
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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 1.2 nm. This disappearance is related to a global contraction of the unit cell resulting from low atomic coordinations at the wire surface. It is shown that a ferroelectric distortion can be recovered under appropriate tensile strain conditions.

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Gregory Geneste, Eric Bousquet, Javier Junquera, Philippe Ghosez. 2006-01-27. Finite-size effects in BaTiO3 nanowires. https://doi.org/10.1063/1.2186104

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