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arXiv · 1811.02713

Ferroelectricity in [111]-oriented epitaxially strained SrTiO$_3$ from first principles

Sebastian E. Reyes-Lillo·Karin M. Rabe·Jeffrey B. Neaton
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Abstract

We use first principles density functional theory calculations to investigate the effect of biaxial strain in the low-temperature structural and ferroelectric properties of [111]-oriented SrTiO$_3$. We find that [111] biaxial strain, achievable by coherent epitaxial growth along the [111] direction, induces structural distortions in SrTiO$_3$ that are not present in either bulk or [001]-oriented SrTiO$_3$. Under [111] biaxial strain, SrTiO$_3$ displays ferroelectricity at tensile strain, and paraelectricity at compressive strain. We compute the phonon spectrum and macroscopic polarization of SrTiO$_3$ as a function of [111] biaxial strain, and relate our results to the predictions of the free energy phenomenological model of Pertsev, Tagantsev and Setter [Phys. Rev. B 61, 825 (2000); Phys. Rev. B 65, 219901 (2002)].

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Sebastian E. Reyes-Lillo, Karin M. Rabe, Jeffrey B. Neaton. 2018-11-07. Ferroelectricity in [111]-oriented epitaxially strained SrTiO$_3$ from first principles. https://doi.org/10.1103/physrevmaterials.3.030601

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