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Phonon in SrTiO$_3$ under finite electric fields

Ivan I. Naumov·Huaxiang Fu
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Abstract

We propose an efficient approach within the density-functional theory to determine the phonon structure of infinite solids under finite electric fields. We apply this approach to technological SrTiO$_3$, predicting many unusual properties--including a giant frequency shift, anomalous piezoelectric response, as well as striking dielectric tunability. A microscopic understanding for individual phonon modes under finite electric fields is also provided.

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Ivan I. Naumov, Huaxiang Fu. 2004-09-13. Phonon in SrTiO$_3$ under finite electric fields. https://arxiv.org/abs/cond-mat/0409330

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