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arXiv · 1910.11155

The effect of Non-centrosymmetricity on optical and electronic properties of cubic BaHfO$_{3}$ perovskite structure

Tewodros Eyob·Kenate Nemera·Lemi Demeyu
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Abstract

The effect of Non-centrosymmetricity on electronic and optical properties has been investigated using grid based projector augmented wave method code GPAW. The calculation of band gap using GLLB-SC which improves on the exchange potential and explicitly estimates the derivative discontinuity is similar to experimental result. Ferro-electricity of BaHfO$_{3}$ is increased as lattice distortion kept on increasing. Static dielectric constant, index of refraction only show slight change and in good agreement with experimental and other results. Absorption reaches highest peaks in visible frequency range, and absorption coefficient decreased as light goes through BaHfO$_{3}$ bulk, this in turn enhance excitonic property. Exciton binding energy increased over lattice distortion sites. The presented results are important in connection with development of typical perovskite optoelectronic device properties.

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Tewodros Eyob, Kenate Nemera, Lemi Demeyu. 2019-10-24. The effect of Non-centrosymmetricity on optical and electronic properties of cubic BaHfO$_{3}$ perovskite structure. https://doi.org/10.1016/j.cocom.2020.e00524

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