Theory of the Reentrant Charge-Order Transition in the Manganites

C. Stephen Hellberg

doi:10.1063/1.1358326

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Theory of the Reentrant Charge-Order Transition in the Manganites

C. Stephen Hellberg

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Abstract

A theoretical model for the reentrant charge-order transition in the manganites is examined. This transition is studied with a purely electronic model for the Mn electrons: the extended Hubbard model. The electron-phonon coupling results in a large nearest-neighbor repulsion between electrons. Using a finite-temperature Lanczos technique, the model is diagonalized on a 16-site periodic cluster to calculate the temperature-dependent phase boundary between the charge-ordered and homogeneous phases. A reentrant transition is found. The results are discussed with respect to the specific topology of the 16-site cluster.

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C. Stephen Hellberg. 2000-10-26. Theory of the Reentrant Charge-Order Transition in the Manganites. https://doi.org/10.1063/1.1358326

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