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arXiv · 0802.0653

Electronic correlations decimate the ferroelectric polarization of multiferroic HoMn2O5

Gianluca Giovannetti·Jeroen van den Brink
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Abstract

We show that electronic correlations decimate the intrinsic ferroelectric polarization of the recently discovered class of multiferroic manganites RMn$_2$O$_5$, where R is a rare earth element. Such is manifest from {\it ab initio} bandstructure computations that account for the strong local Coulomb interactions between the manganese 3d electrons --the root of magnetism in these materials. When including these the computed electronic, magnetic and lattice structure of multiferroic HoMn$_2$O$_5$ results in an amplitude and direction of polarization that is in accordance with experiment. The microscopic mechanism behind the decimation is a near cancellation of the ionic polarization induced by ferroelectric lattice displacements and the electronic one caused by valence charge redistributions.

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Gianluca Giovannetti, Jeroen van den Brink. 2008-02-05. Electronic correlations decimate the ferroelectric polarization of multiferroic HoMn2O5. https://doi.org/10.1103/physrevlett.100.227603

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