Structural, Electrical, And Magnetic Properties Of Polycrystalline Fe3-Xptxo4 (0 <= X <= 0.10) Films

Polycrystalline Fe(3-x)PtxO(4) films have been prepared by cosputtering at room-temperature. The composition, magnetization and Hall effect measurements indicate that Pt ions have been doped at B-sites. The resistivity is dominated by fluctuation-induced tunneling and decreases with increasing x. The absolute magnetoresistance at room-temperature is above 7% for x <= 0.07. The carrier concentration is lower than that of the single-crystal and epitaxial films. A scaling relation of sigma(xy) alpha sigma(xx) between the Hall and longitudinal conductivities is obtained for all samples, which fits well with the recent developed universal scaling theory. The decreasing trend of the exponent n from 1.72 to 1.57 with increasing x could be qualitatively ascribed to the influence of the Pt2+ ions on the magnetic scattering center concentration of the B-sites Fe2+ ions. These findings make the Fe3-xPtxO4 film a useful candidate for spintronic or extraordinary Hall effect devices applications. (C) 2011 American Institute of Physics. [doi:10.1063/1.3563080]