Inverse giant magnetoresistance

Inverse giant magnetoresistance (GMR) is obtained in multilayers alternating two ferromagnetic layers F-1 and F-2 with different asymmetry of spin scattering, alpha(1)>1 and alpha(2)>1. This is clearly demonstrated in the simple spin-valve system with perpendicular magnetization Fe1-xVx/Au/Co. With respect to Fe, and FeV alloys with x = 0.18 and 0.29 exhibit an inversion of the spin scattering coefficients (alpha(Fe)>1, alpha(FeV)<1) due to the change of the densities of states at the Fermi level. The inverse MR of FeV/Au/Co is studied as a function of FeV layer thickness and temperature and compared to calculations based on the Camley-Barnas model. The data show that the inverse GMR is due to the bulk scattering within the FeV layer, which coexists with a substantial interface scattering favoring normal GMR. (C) 1996 American Institute of Physics.