Achieving large magnetoresistance in Sr2FeMoO6 thin films

Abstract

In order to find a way to achieve large magnetoresistance in thin films of Sr2FeMoO6, structural, magnetic, and transport properties were systematically investigated for the films grown on SrTiO3 substrates under different conditions. Crystallinity, morphology, resistivity, and magnetization of the films depended sensitively on the growth temperature and post-anneal treatment. The film grown at 935 degreesC and post-annealed at the same temperature for an hour displayed both large resistance and magnetoresistance; the low-field magnetoresistance, in particular, was as large as that of a polycrystalline bulk. Structural analysis revealed that the film possessed large grains, and the large magnetoresistance is accounted for in terms of spin-polarized tunneling between these grains. (C) 2005 American Institute of Physics.