Giant Magnetoresistance in Granular Type (Co- Ag) /Ag Multilayers

The dependence of giant magnetoresistance of sputtered granular type (Co-Ag)/Ag multilayers on the thickness of Ag layers and magnetic layers with varying Co content in the magnetic layers was studied. The magnetoresistance ratio ΔR/R was found to be enhanced by 2-7 times comparing with the single layer granular films. The enhancement was explained by the antiferromagnetic coupling due to magnetostatic interaction between the Co clusters in neighboring magnetic layers.