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Ferromagnetic Polarons in Manganites

C. D. Batista·J. Eroles·M. Avignon·B. Alascio
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Abstract

Using the Lanczos method in linear chains we study the double exchange model in the low concentration limit, including an antiferromagnetic super-exchange K. In the strong coupling limit we find that the ground state contains ferromagnetic polarons whose length is very sensitive to the value of K/t. We investigate the dispersion relation, the trapping by impurities, and the interaction between these polarons. As the overlap between polarons increases, by decreasing K/t, the effective interaction between them changes from antiferromagnetic to ferromagnetic. The scaling to the thermodynamic limit suggests an attractive interaction in the strong coupling regime (J_h > t) and no binding in the weak limit (J_h \simeq t).

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C. D. Batista, J. Eroles, M. Avignon, B. Alascio. 2000-08-24. Ferromagnetic Polarons in Manganites. https://doi.org/10.1103/physrevb.62.15047

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