HIGH-CURRENT DENSITY SELF-FIELD EFFECTS AND LOW-FREQUENCY NOISE IN NIFE AG GMR MULTILAYERS/

High current densities (10(6)-10(7) A/cm(2)) produce magnetic fields w hich can induce antiparallel magnetic alignment in large (16 mu m and 8 mu m) NiFe/Ag thin film multilayer devices. We induce GMR in unannea led devices which normally do not display GMR. We find multiple peaks in the magnetoresistance curves of annealed and unannealed devices. An alysis of the positions and shapes of these magnetoresistance peaks pr ovides a new set of tools for determining the micromagnetic structure of the multilayers. Our magneto-optical Kerr effect data and low frequ ency noise data correlate with the magnetoresistance peaks and may yie ld further information about layer-layer interactions and domain struc ture.