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Charge-ordered ferromagnetic phase in manganites

Tran Minh-Tien
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Abstract

A mechanism for charge-ordered ferromagnetic phase in manganites is proposed. The mechanism is based on the double exchange in the presence of diagonal disorder. It is modeled by a combination of the Ising double-exchange and the Falicov-Kimball model. Within the dynamical mean-field theory the charge and spin correlation function are explicitely calculated. It is shown that the system exhibits two successive phase transitions. The first one is the ferromagnetic phase transition, and the second one is a charge ordering. As a result a charge-ordered ferromagnetic phase is stabilized at low temperature.

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Tran Minh-Tien. 2003-02-17. Charge-ordered ferromagnetic phase in manganites. https://doi.org/10.1103/physrevb.67.144404

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