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Charge order versus Zener polarons: ferroelectricity in manganites

Dmitry V. Efremov·Jeroen van den Brink·Daniel I. Khomskii
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Abstract

We show that in manganites close to half-doping novel non-bipartite magnetic phases appear due to the interplay between double exchange, superexchange and orbital ordering. In considerable part of the phase diagram the groundstate has a magnetic order that is intermediate between the canonical magnetic CE-phase and a state that we identify as the recently observed Zener polaron state. The intermediate phase shows a type of charge ordering that breaks inversion symmetry and is therefore predicted to be ferroelectric.

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Dmitry V. Efremov, Jeroen van den Brink, Daniel I. Khomskii. 2003-06-25. Charge order versus Zener polarons: ferroelectricity in manganites. https://arxiv.org/abs/cond-mat/0306651

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