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arXiv · 1512.00362

Controlling the cation distribution and electric polarization with epitaxial strain in Aurivillius-phase Bi$_5$FeTi$_3$O$_{15}$

Axiel Yaël Birenbaum·Claude Ederer
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Abstract

This work explores the impact of in-plane bi-axial (epitaxial) strain on the cation distribution and electric polarization of the Aurivillius-phase compound Bi$_5$FeTi$_3$O$_{15}$ using first-principles electronic structure calculations. Our calculations indicate that the site preference of the Fe$^{3+}$ cation can be controlled via epitaxial strain. Tensile strain enhances the preference for the inner sites within the perovskite-like layers of the Aurivillius-phase structure, whereas compressive strain favors occupation of the outer sites within the perovskite-layers, i.e., the sites close to the Bi$_2$O$_2$ layer. Controlling the distribution of the magnetic cations offers the possibility to control magnetic order in this magnetically dilute system. Furthermore, the magnitude of the electric polarization is strongly strain-dependent, increasing under tensile strain and decreasing under compressive strain. Analysis of the Born effective charges reveals strongly anomalous charges, both of the Bi$^{3+}$ cations and the Ti$^{4+}$ cations.

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Axiel Yaël Birenbaum, Claude Ederer. 2016-02-01. Controlling the cation distribution and electric polarization with epitaxial strain in Aurivillius-phase Bi$_5$FeTi$_3$O$_{15}$. https://doi.org/10.1063/1.4942668

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