Polaron transport in the paramagnetic phase of electron-doped manganites
نویسندگان
چکیده
The electrical resistivity, Hall coefficient, and thermopower as functions of temperature are reported for lightly electron-doped Ca1−xLaxMnO3 0 x 0.10 . Unlike the case of hole-doped ferromagnetic manganites, the magnitude and temperature dependence of the Hall mobility H 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 5.4 with a band effective mass m* 4.3m0 and a polaron mass mp 10m0.
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