Magnetic field mediated low-temperature resistivity upturn in electron-doped La1-xHfxMnO3 manganite oxides

The low-temperature transport properties were systematically studied on the electron-doped polycrystalline La1-xHfxMnO3(x=0.2 and 0.3) compounds at the presence of external magnetic fields. The resistivity of all samples exhibits a generally low-temperature resistance upturn behavior under zero magnetic field at the temperature of T-min, which first shifts towards lower temperature at low magnetic field (H<0.75 T) and then moves back to higher temperature as magnetic fields increase, which is greatly different with the previous results on the hole-doped manganites. The best fitting of low-temperature resistivity could be made by considering both electron-electron (e-e) interactions in terms of T-1/2 dependence and Kondo-like spin dependent scattering in terms of lnT dependence at all magnetic fields. Our results will be meaningful to understand the underlying physical mechanism of low-temperature resistivity minimum behavior in the electron-doped manganites. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4770320]