Magnetotransport properties of La2/3Sr1/3MnO3 thin film

We report the temperature and magnetic field dependence of the resistivity of La2/3Sr1/3MnO3 thin film over a wide temperature range and in high magnetic fields up to 20 T. Both above and below the ferromagnetic (FM) transition, the field dependence of the magnetoresistance (MR) can be described well using the extended Mott hopping conduction model. The large MR is proportional to the Brillouin function B-J in the FM phase and to B-J(2) in the paramagnetic state which is consistent with this model. The value of spin moment J deduced from the temperature and magnetic field dependence of the MR is large (similar to60) in the vicinity of the FM transition. This large value of J has been attributed to the presence of magnetic clusters due to the short-range FM ordering. (C) 2002 American Institute of Physics