Magnetostatic mechanism for field-sensitivity of magnetoresistance in discontinous magnetic multilayers

We derive an expression for the inter-layer magnetostatic coupling which governs the field-sensitivity of the giant magnetoresistance in the thin discontinous magnetic multilayers of composition (Ni80Fe20)/Ag recently discovered by T.L. Hylton and coworkers. This expression provides estimates of the width G of the magnetic discontinuity needed to account for the external fields used to obtain the published experimental magnetoresistance data. The results are G = 10 Å after the anneal which maximizes the saturation magnetoresistance and G ≈ 6 Å after the anneal which maximizes its field-sensitivity. © 1994.