Current distribution in spin-valve structures

An analysis of the current distribution within a passivated Giant Magnetoresistance Ratio (GMR) sandwich is presented. The magnetic fields produced by the various current components and their affect on the GMR sandwich are examined. Currents in the non-magnetic inner layer of the sandwich and the passivation layer are seen to decrease the resistance change and GMR signal obtained with a given source current. Methods for determining the amount of current shunted by the non-magnetic layers are explained. Analysis of voltage versus field measurements from several samples show that 10% and 20% of the current is being shunted through 50 Å and 100 Å Ta passivation layers, respectively, and that 13% to 34% of the remaining current is shunted through the non-magnetic inner layer