Magnetoresistance of epitaxial thin films of ferromagnetic metallic oxide SrRuO3 with different domain structures

We have studied the magnetoresistive behavior of epitaxial thin films of the conductive ferromagnetic oxide SrRuO3 with different domain structures grown on both miscut (001) SrTiO3 and exact (001) LaAlO3 substrates. A strong anisotropic magnetoresistance (MR) has been observed in the single domain SrRuO3 thin film on miscut (001) SrTiO3 substrate. In contrast, the SrRuO3 thin film on (001) LaAlO3 substrate shows identical MR behavior in two orthogonal directions on the film due to the presence of 90 degrees domains in the plane. For both the films, large negative magnetoresistance effects (similar to 10%) were observed when the current and the applied magnetic field are parallel. This is attributed to a reduction in spin fluctuations near T-c and to magnetization rotation leading to a change in the angle between the current and magnetization at low temperatures. (C) 1997 American Institute of Physics.