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Jahn-Teller, Charge and Magnetic Ordering in half-doped Manganese Oxides

S. Fratini·D. Feinberg·M. Grilli
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Abstract

The phase diagram of half-doped manganite systems of formula A_{0.5}A'_{0.5}MnO_3 is investigated within a single-orbital model incorporating magnetic double-exchange and superexchange, together with intersite Coulomb and electron-lattice interactions. Strong Jahn-Teller and breathing mode deformations compete together and result in shear lattice deformations. The latters stabilize the charge-ordered CE-type phase, which undergo first-order transitions with temperature or magnetic field to either Ferromagnetic metallic or Paramagnetic insulating phases. An essential feature is the self-consistent screening of Coulomb and electron-phonon interactions in the ferromagnetic phase.

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S. Fratini, D. Feinberg, M. Grilli. 2000-11-24. Jahn-Teller, Charge and Magnetic Ordering in half-doped Manganese Oxides. https://doi.org/10.1007/s100510170123

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