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arXiv · 1306.1839

Strain-Induced Hybrid Improper Ferroelectricity in Simple Perovskites from First Principles

Qibin Zhou·Karin M. Rabe
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Abstract

We performed first principles calculations for epitaxially strained orthorhombic CaTiO$_3$. The computational results reveal the existence of a metastable ferroelectric phase at compressive strain with unexpected in-plane polarization. Symmetry analysis indicates that two distortion modes at the X point combine to induce the polarization, leading to characterization as a hybrid improper ferroelectric. Our work demonstrates a mechanism for improper ferroelectricity in simple perovskites without the need for symmetry lowering by layering or cation ordering.

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Qibin Zhou, Karin M. Rabe. 2013-08-25. Strain-Induced Hybrid Improper Ferroelectricity in Simple Perovskites from First Principles. https://arxiv.org/abs/1306.1839

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