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arXiv · 0811.2344

Engineering multiferroism in CaMnO$_3$

Satadeep Bhattacharjee·Eric Bousquet·Philippe Ghosez
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Abstract

From first-principles calculations, we investigate the structural instabilities of CaMnO$_3$. We point out that, on top of a strong antiferrodistortive instability responsible for its orthorhombic ground-state, the cubic perovskite structure of CaMnO$_3$ also exhibit a weak ferroelectric instability. Although ferroelectricity is suppressed by antiferrodistortive oxygen motions, we show that it can be favored using strain or chemical engineering in order to make CaMnO$_3$ multiferroic. We finally highlight that the FE instability of CaMnO$_3$ is Mn-dominated. This illustrates that, contrary to the common believe, ferroelectricity and magnetism are not necessarily exclusive but can be driven by the same cation.

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Satadeep Bhattacharjee, Eric Bousquet, Philippe Ghosez. 2008-11-21. Engineering multiferroism in CaMnO$_3$. https://doi.org/10.1103/physrevlett.102.117602

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