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Lattice-Spin Mechanism in Colossal Magnetoresistant Manganites

J. A. Verges·V. Martin-Mayor·L. Brey
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Abstract

We present a single-orbital double-exchange model, coupled with cooperative phonons (the so called breathing-modes of the oxygen octahedra in manganites). The model is studied with Monte Carlo simulations. For a finite range of doping and coupling constants, a first-order Metal-Insulator phase transition is found, that coincides with the Paramagnetic-Ferromagnetic phase transition. The insulating state is due to the self-trapping of every carrier within an oxygen octahedron distortion.

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J. A. Verges, V. Martin-Mayor, L. Brey. 2002-02-21. Lattice-Spin Mechanism in Colossal Magnetoresistant Manganites. https://arxiv.org/abs/cond-mat/0109127

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