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arXiv · 1307.0132

First-principles theory and calculation of flexoelectricity

Jiawang Hong·David Vanderbilt
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Abstract

We develop a general and unified first-principles theory of piezoelectric and flexoelectric tensor, formulated in such a way that the tensor elements can be computed directly in the context of density-functional calculations, including electronic and lattice contributions. We introduce a practical supercell-based methods for calculating the flexoelectric coefficients from first principles, and demonstrate them by computing the coefficients for a variety of cubic insulating materials, including C, Si, MgO, NaCl, CsCl, BaZrO3, BaTiO3, PbTiO3 and SrTiO3.

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Jiawang Hong, David Vanderbilt. 2013-06-29. First-principles theory and calculation of flexoelectricity. https://doi.org/10.1103/physrevb.88.174107

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