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Jahn-Teller Effect and Superexchange in Half-Doped Manganites

Olga Sikora·Andrzej M. Oles
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Abstract

We investigate the stability of the charge exchange (CE) phase within a microscopic model which describes a single plane as in La$_{0.5}$Sr$_{1.5}$MnO$_4$. The model includes Coulomb interactions (on-site and intersite), the Jahn-Teller term and the superexchange interactions due to $e_g$ and $t_{2g}$ electrons. By investigating the phase diagram at T=0 in mean-field approximation we conclude that the superexchange interactions can stabilize the CE phase, but only if they are stronger than estimated from spectroscopy.

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Olga Sikora, Andrzej M. Oles. 2003-03-12. Jahn-Teller Effect and Superexchange in Half-Doped Manganites. https://doi.org/10.1002/pssb.200301684

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