Effects of magnetic field on the manganite-based bilayer junction

An oxide bilayer junction has been fabricated by growing a La0.32Pr0.35Ca0.33MnO3 film on 0.5 wt % Nb-doped SrTiO3 crystal, and its behavior under magnetic field is experimentally studied. It is found that external field greatly affected the rectifying property and the resistance of the junction, causing an extremely large magnetoresistance. The most striking observation of the present work is that the magnetoresistance of the junction can be either positive or negative, depending on temperature and applied current, and is asymmetric with respect to the direction of the bias current. These results reveal the great potential of the manganites in configuring artificial devices. (C) 2004 American Institute of Physics.