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arXiv · 1401.7656

Magnetic polaron structures in the one-dimensional double and super-exchange model

E. Vallejo·F. López-Urías·O. Navarro·M. Avignon
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Abstract

An analytical and numerical study of the one-dimensional double and super-exchange model is presented. A phase separation between ferromagnetic and anti-ferromagnetic phases occurs at low super-exchange interaction energy. When the super-exchange interaction energy gets larger, the conduction electrons are self-trapped within separate small magnetic polarons. These magnetic polarons contain a single electron inside two or three sites depending on the conduction electron density and form a Wigner crystallization. A new phase separation is found between these small polarons and the anti-ferromagnetic phase. Our results could explain the spin-glass-like behavior observed in the nickelate one-dimensional compound Y(2-x)CaxBaNiO5.

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E. Vallejo, F. López-Urías, O. Navarro, M. Avignon. 2014-01-29. Magnetic polaron structures in the one-dimensional double and super-exchange model. https://doi.org/10.1016/j.ssc.2008.11.001

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