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The small polaron crossover transition in colossal magnetoresistance (CMR) manganites

Unjong Yu·B. I. Min
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Abstract

Based on the combined model of the double exchange and the polaron, we have studied the small-to-large polaron crossover transition and explored its effects on the magnetic and transport properties in colossal magnetoresistance (CMR) manganites. We have used the variational Lang-Firsov canonical transformation, and shown that the magnetic and transport properties of both high and low $T_C$ manganites are well described in terms of a single formalism. We have reproduced the rapid resistivity drop below $T_C$, a realistic CMR ratio, and the {\it first-order-like} sharp magnetic phase transition, which are observed in low $T_C$ manganites.

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Unjong Yu, B. I. Min. 1999-06-17. The small polaron crossover transition in colossal magnetoresistance (CMR) manganites. https://arxiv.org/abs/cond-mat/9906263

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