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arXiv · 1204.5106

Ferroelectricity induced by cooperative orbital ordering and Peierls instability

Paolo Barone·Silvia Picozzi
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Abstract

A general mechanism by which orbital ordering, coupled to Peierls-like lattice distortions, can induce an electronic switchable polarization is discussed within a model Hamiltonian approach in the context of the modern theory of polarization. By using a Berry-phase approach, a clear picture emerges in terms of Wannier-function centers and orbital occupancies. The proposed mechanism may apply to oxide spinels whose electronic structure has effective one-dimensional character, such as CdV$_2$O$_4$, recently proposed to display multiferroic behaviour.

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Paolo Barone, Silvia Picozzi. 2012-04-23. Ferroelectricity induced by cooperative orbital ordering and Peierls instability. https://doi.org/10.1103/physrevb.85.214101

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