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arXiv · 1306.0161

Strain enhancement of high-k dielectric response in (La/Sc)2 O3 and LaScO3 : an ab-initio study

Stas M. Avdoshenko·Alejandro Strachan
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Abstract

We use density functional theory within the generalized gradient approximation to characterize the dielectric response of rare earth oxides: (La,Sc)2 O3 bixbyite, and LaScO3 perovskite. We focus on the role of strain on the phonon contribution of the dielectric constant and find that, contrary to the classical expectation based on the Clausius-Mossotti relation, tensile volumetric strain and volume-conserving bi- axial strain on the order of +/-1% can lead to an increase in dielectric constant of up to 20%. The insight into the atomic mechanisms responsible for these effects and the quantitative results in this paper can contribute to the development and understanding of high-κ materials.

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Stas M. Avdoshenko, Alejandro Strachan. 2013-06-02. Strain enhancement of high-k dielectric response in (La/Sc)2 O3 and LaScO3 : an ab-initio study. https://arxiv.org/abs/1306.0161

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