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The ferroelectric transition in YMnO$_3$ from first principles

Craig J. Fennie·Karin M. Rabe
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Abstract

We have studied the structural phase transition of multiferroic YMnO$_3$ from first principles. Using group-theoretical analysis and first-principles density functional calculations of the total energy and phonons, we perform a systematic study of the energy surface around the prototypic phase. We find a single instability at the zone-boundary which couples strongly to the polarization. This coupling is the mechanism that allows multiferroicity in this class of materials. Our results imply that YMnO$_3$ is an improper ferroelectric. We suggest further experiments to clarify this point.

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Craig J. Fennie, Karin M. Rabe. 2005-10-18. The ferroelectric transition in YMnO$_3$ from first principles. https://doi.org/10.1103/physrevb.72.100103

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