ENHANCED GIANT MAGNETORESISTANCE IN FE/CR MULTILAYER FILMS BY CR ALLOYING OF THE FE LAYERS

The effect of the Cr alloying addition to the Fe layers in the Fe/Cr superlattice films [Fe(15 angstrom)/Cr(tangstrom)]30), (t=8-20) on the magnetoresistance behavior has been investigated. The alloyed superlattice films exhibited significantly improved giant magnetoresistance effect (DELTAR/R is similar to 12.2% at 4.2 K) as compared to the unalloyed Fe/Cr multilayer films (DELTAR/R is similar to 6.9%). Both films exhibit DELTAR/R dependence on the thickness of the Cr layer with the maximum DELTAR/R occurring at approximately 10 angstrom thickness. The M-H loops indicate that antiferromagnetic coupling exists in both films, which is believed to be responsible for the observed giant magnetoresistance. The improvement in DELTAR/R in the Cr-alloyed superlattice films is attributed to the stronger spin-dependent scattering of conduction electrons.