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Short-circuit boundary conditions in ferroelectric PbTiO$_3$ thin films

Alexie M. Kolpak·Na Sai·Andrew M. Rappe
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Abstract

We examine the application of short-circuit electrical boundary conditions in density functional theory calculations of ferroelectric thin films. Modeling PbTiO$_3$ films with Pt electrodes, we demonstrate that under periodic boundary conditions of supercells, short-circuit conditions for the electrodes are equivalently satisfied in two repeated slab geometries: a PbTiO$_3$/metal superlattice geometry and a periodic metal/PbTiO$_3$/metal/vacuum geometry, where the metal is Pt or SrRuO$_3$. We discuss the benefits of each geometry in the study of ferroelectricity in thin films.

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Alexie M. Kolpak, Na Sai, Andrew M. Rappe. 2006-05-24. Short-circuit boundary conditions in ferroelectric PbTiO$_3$ thin films. https://doi.org/10.1103/physrevb.74.054112

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