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arXiv · 2203.16677

First-principles Landau-like potential for BiFeO$_3$ and related materials

Natalya S. Fedorova·Dmitri E. Nikonov·Hai Li·Ian A. Young·Jorge Íñiguez
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Abstract

In this work we introduce the simplest, lowest-order Landau-like potential for BiFeO$_3$ and La-doped BiFeO$_3$ as an expansion around the paraelectric cubic phase in powers of polarization, FeO$_6$ octahedral rotations and strains. We present an analytical approach for computing the model parameters from density functional theory. We illustrate our approach by computing the potentials for BiFeO$_3$ and La$_{0.25}$Bi$_{0.75}$FeO$_3$ and show that, overall, we are able to capture the first-principles results accurately. The computed models allow us to identify and explain the main interactions controlling the relative stability of the competing low-energy phases of these compounds.

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Natalya S. Fedorova, Dmitri E. Nikonov, Hai Li, Ian A. Young, Jorge Íñiguez. 2022-03-30. First-principles Landau-like potential for BiFeO$_3$ and related materials. https://doi.org/10.1103/physrevb.106.165122

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