Effects of interfacial roughness on the magnetoresistance of magnetic metallic multilayers

The Boltzmann equation is solved for a system consisting of a ferromagnetic--normal-metallic multilayer. The in-plane magnetoresistance of iron/chromium and iron/copper superlattices is calculated for varying interfacial geometric random roughness with no lateral coherence: correlated (quasiperiodic) roughness; and varying chemical composition of the interfaces. The interplay between these three aspects of the interfaces may enhance or suppress the magnetoresistance, depending on whether it increases or decreases the asymmetry in the spin-dependent scattering of the conduction electrons. Properties of the interfaces relevant to the giant negative magnetoresistance are discussed.