Structural analysis and magnetic properties of (Pt/Co)3/PttPt/IrMn multilayers

Structural and magnetic investigations of Ta-3 nm/[(Pt-2 nm/Co-0.4 nm)(3)/Pt-tPt/IrMn7 nm](7)/Pt-10 nm multilayers with t(Pt)=0 and t(Pt)=0.4 nm have been carried out using x-ray reflectometry, tomographic atom probe, and superconducting quantum interference device magnetometry. The structural investigations show that the Co/IrMn interface is more diffuse in the absence of the Pt spacer. The consequences on the magnetic properties are discussed. The exchange-bias field and the anisotropy direction of these two specimens are analyzed in comparison to Ta-3 nm/[(Pt-2 nm/Co-0.4 nm)(3)/Pt-tPt/IrMn7 nm]/Pt-10 nm multilayers containing only one ferromagnetic/antiferromagnetic repeat and correlated with the structural investigations.