HOW TO ISOLATE EFFECTS OF SPIN-FLIP SCATTERING ON GIANT MAGNETORESISTANCE IN MAGNETIC MULTILAYERS

A technique is described for isolating effects of finite spin diffusio n lengths on the magnetoresistance (MR) of magnetic multilayers at low temperatures by measuring the MR with the current perpendicular to th e layer planes. Applying this technique to relatively concentrated Co/ AgMn and Co/CuMn multilayers yields large effects, generally consisten t with expectations from a theory by Valet and Fert [Phys. Rev. B 48, 7099 (1993)]. However, some complicating issues still need to be resol ved.