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Polaron Transport in the Paramagnetic Phase of Electron-Doped Manganites

J. L. Cohn·C. Chiorescu·J. J. Neumeier
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Abstract

The electrical resistivity, Hall coefficient, and thermopower as functions of temperature are reported for lightly electron-doped Ca(1-x)La(x)MnO(3)(0 <= x <= 0.10). Unlike the case of hole-doped ferromagnetic manganites, the magnitude and temperature dependence of the Hall mobility for these compounds is found to be inconsistent with small-polaron theory. The transport data are better described by the Feynman polaron theory and imply intermediate coupling (alpha \~ 5.4) with a band effective mass, m*~4.3 m_0, and a polaron mass, m_p ~ 10 m_0.

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J. L. Cohn, C. Chiorescu, J. J. Neumeier. 2005-04-12. Polaron Transport in the Paramagnetic Phase of Electron-Doped Manganites. https://doi.org/10.1103/physrevb.72.024422

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