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arXiv · 1609.08246

Multiferroic Bi$_2$NiMnO$_6$ Thin Films: A Computational Prediction

Oswaldo Diéguez·Jorge Íñiguez
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Abstract

We report first-principles calculations for one of the few materials that is believed to be a ferroelectric ferromagnet, Bi$_2$NiMnO$_6$. Our calculations show that, contrary to what it has been reported so far, bulk Bi$_2$NiMnO$_6$ does not have a polarization. Instead, like BiMnO$_3$, it crystallizes into a centrosymmetric structure with space group $C2/c$. We also predict that Bi$_2$NiMnO$_6$ will indeed be a ferroelectric ferromagnet if it is grown as an epitaxial film on a substrate with in-plane square symmetry and a lattice constant around 4~Å, such as BaTiO$_3$ or PbZr$_{1-x}$Ti$_{x}$O$_{3}$.

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Oswaldo Diéguez, Jorge Íñiguez. 2016-09-27. Multiferroic Bi$_2$NiMnO$_6$ Thin Films: A Computational Prediction. https://doi.org/10.1103/physrevb.95.085129

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