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A Microscopic Model of Ferroelectricity in Stress-free PbTiO3 Ultrathin Films

Ph. Ghosez·K. M. Rabe
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Abstract

The ground-state polarization of PbTiO3 thin films is studied using a microscopic effective Hamiltonian with parameters obtained from first-principles calculations. Under short-circuit electrical boundary conditions, (001) films with thickness as low as three unit cells are found to have a perpendicularly polarized ferroelectric ground state with significant enhancement of the polarization at the surface.

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Ph. Ghosez, K. M. Rabe. 2000-03-16. A Microscopic Model of Ferroelectricity in Stress-free PbTiO3 Ultrathin Films. https://doi.org/10.1063/1.126469

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