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Spin-dependent transport in phase-separated manganites

K. I. Kugel·A. L. Rakhmanov·A. O. Sboychakov·M. Yu. Kagan·I. V. Brodsky·A. V. Klaptsov
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Abstract

Starting from the assumption that ferromagnetically correlated regions exist in manganites even in the absence of long-range magnetic order, we construct a model of charge transfer due to the spin-dependent tunnelling of charge carriers between such regions. This model allows us to analyze the temperature and magnetic field dependence of resistivity, magnetoresistance, and magnetic susceptibility of phase-separated manganites in the temperature range corresponding to non-metallic behavior. The comparison of theoretical and experimental results reveals the main characteristics of the phase-separated state.

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K. I. Kugel, A. L. Rakhmanov, A. O. Sboychakov, M. Yu. Kagan, I. V. Brodsky, A. V. Klaptsov. 2003-12-11. Spin-dependent transport in phase-separated manganites. https://arxiv.org/abs/cond-mat/0312294

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