Conservation of dielectric constant upon amorphization in perovskite oxides

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.

5 pages, 3 figures

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Cited by in corpus (1)

• Dielectric constant boost in amorphous sesquioxides