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Enhanced polarization in strained BaTiO$_3$ from first principles

J. B. Neaton·C. -L. Hsueh·K. M. Rabe
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Abstract

The structure, polarization, and zone-center phonons of bulk tetragonal BaTiO$_3$ under compressive epitaxial stress are calculated using density functional theory within the local density approximation. The polarization, computed using the Berry-phase formalism, increases with increasing tetragonality and is found to be enhanced by nearly 70% for the largest compressive misfit strain considered (-2.28%). The results are expected to be useful for the analysis of coherent epitaxial BaTiO$_3$ thin films and heterostructures grown on perovskite substrates having a smaller lattice constant, such as SrTiO$_3$.

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J. B. Neaton, C. -L. Hsueh, K. M. Rabe. 2002-04-23. Enhanced polarization in strained BaTiO$_3$ from first principles. https://arxiv.org/abs/cond-mat/0204511

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