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arXiv · 0803.0478

Conservation of dielectric constant upon amorphization in perovskite oxides

Pietro Delugas·Vincenzo Fiorentini·Alessio Filippetti·Geoffrey Pourtois
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Abstract

We report calculations indicating that amorphous RAO$_3$ oxides, with R and A trivalent cations, have approximately the same static dielectric constant as their perovskite crystal phase. The effect is due to the disorder-activated polar response of non-polar crystal modes at low frequency, which compensates a moderate but appreciable reduction of the ionic dynamical charges. The dielectric response was studied via density-functional perturbation theory. Amorphous samples were generated by molecular dynamics melt-and-quench simulations.

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Pietro Delugas, Vincenzo Fiorentini, Alessio Filippetti, Geoffrey Pourtois. 2008-03-04. Conservation of dielectric constant upon amorphization in perovskite oxides. https://doi.org/10.1103/physrevb.76.104112

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