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arXiv · 0905.4481

Striped Multiferroic Phase in Double-Exchange Model for Quarter-Doped Manganites

Shuai Dong·Rong Yu·J. -M. Liu·Elbio Dagotto
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Abstract

The phase diagram of quarter-hole-doped perovskite manganites is investigated using the doubleexchange model. An exotic striped type-II multiferroic phase, where 25% of the nearest-neighbor spin couplings are orthogonal to each other, is found in the narrow-bandwidth region. Comparing with the spiral-spin ordering phase of undoped manganites, the multiferroic Curie temperature of the new phase is estimated to be ~4 times higher, while the ferroelectric polarization is similar in magnitude. Our study provides a path for noncollinear spin multiferroics based on electronic self-organization, different from the traditional approach based on superexchange frustration.

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Shuai Dong, Rong Yu, J. -M. Liu, Elbio Dagotto. 2009-09-07. Striped Multiferroic Phase in Double-Exchange Model for Quarter-Doped Manganites. https://doi.org/10.1103/physrevlett.103.107204

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