POSITIVE GIANT MAGNETORESISTANCE IN A FE3O4 SRTIO3/LA0.7SR0.3MNO3 HETEROSTRUCTURE/

A very large positive magnetoresistance (MR) has been discovered in a Fe3O4/SrTiO3/La0.7Sr0.3MnO3 heterostructure for the transport perpendi cular to the layer planes and applied magnetic field in the film plane . The observed MR features do not show any obvious correlation with th e hysteresis behavior of the ferromagnetic bilayers. A possible explan ation of these results is given in terms of the relative differences i n the majority and minority spin bands of the two ferromagnetic layers and the field induced modifications of domain structures therein. (C) 1998 American Institute of Physics. [S0003-6951(98)02031-2].