Spin Dependent Hopping and Colossal Negative Magnetoresistance in EpitaxialFilms in Fields up to 50 T
- 2 November 1998
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 81 (18), 3980-3983
- https://doi.org/10.1103/physrevlett.81.3980
Abstract
The low carrier mobility of the magnetic perovskite implies that the dominant conductivity mechanism is related to Mott hopping. We propose a modification of Mott's original model by taking into account that the hopping barrier depends on the misorientation between the spins of electrons at an initial and a final state in an elementary hopping process. Using this model we deduce a negative-magnetoresistivity scaling proportional to the Brillouin function in the ferromagnetic state and to in the paramagnetic state. Both predictions are in full agreement with the magnetoresistivity measured in pulsed magnetic fields up to 50 T.
Keywords
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