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arXiv · 1302.2006

Improper ferroelectricity and multiferroism in 2HBaMnO$_3$

Julien Varignon·Philippe Ghosez
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Abstract

Using first-principles calculations, we study theoretically the stable 2H hexagonal structure of BaMnO3. We show that from the stable high temperature P63/mmc structure, the compound should exhibit an improper ferroelectric structural phase transition to a P63cm ground state. Combined with its antiferromagnetic properties, 2H-BaMnO3 is therefore expected to be multiferroic at low temperature. The phase transition mechanism in BaMnO3 appears similar to what was reported in YMnO3 in spite of totally different atomic arrangement, cation sizes and Mn valence state.

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Julien Varignon, Philippe Ghosez. 2013-02-08. Improper ferroelectricity and multiferroism in 2HBaMnO$_3$. https://doi.org/10.1103/physrevb.87.140403

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