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The magnetophoresis of water-suspended 4 μm-diameter superparamagnetic beads above topographically patterned, sputter deposited Ti(4 nm)/Au(60 nm)/[Co(0.7 nm)/Au(1 nm)] × 3 multilayers with perpendicular magnetic anisotropy was investigated. The results impressively demonstrate that the magnetic stray field landscape above the stripe structure when superimposed with an external, slowly rotating, field enables the directed transport of magnetic beads across the stripe panel with velocities up to 12 μm s−1.

The perpendicular exchange bias in NiO(antiferromagnet)/Co(ferromagnet) polycrystalline layer films is studied. It is found that the NiO layer forces the Co layer magnetization to be oriented perpendicular to the film plane in a greater thickness range than is found in the Au/Co/Au system. Simultaneously, a large coercivity and a significant perpendicular exchange bias field were observed that are owing to the interlayer exchange bias coupling between NiO and Co, which supports the perpendicular magnetic anisotropy of the Co layer. These findings are confirmed by magnetometry and magnetoresistance measurements.

Magnetization reversal processes in Au/Co/Au-wedge/Co/Au pseudo-spin-valve structures characterized by perpendicular anisotropy of 0.6-nm-thick Co layers were investigated by magneto-optical Kerr effect. The samples were deposited on a Ti/Au buffer layer of differing Au-layer thickness (different surface roughness and crystallite size). The distinctive influence of the buffer layer thickness on the dependences of switching fields, and energy of the effective interlayer coupling, versus Au spacer thickness is presented. In particular, increasing the buffer-layer thickness results in a decrease in the oscillation amplitude of the Ruderman–Kittel–Kasuya–Yosida-type interaction and in the enhancement of the antiferromagnetic coupling related to magnetostatic (orange peel) interactions.

The giant magnetoresistance (GMR), magnetization reversal, and domain structure of magnetron sputtered spin valve [NiFe/Au/Co/Au]N multilayers consisting of ferromagnetic layers with alternating in-plane (NiFe) and out-of-plane (Co) magnetic anisotropy has been investigated. For 0.4 3, the neighboring magnetic layers were observed to be coupled. This coupling is of magnetostatic origin. The effective coupling field, estimated from GMR dependencies, is of the order of 100 kA/m. Micromagnetic simulations confirm that the domain structure of Co layers influences the behavior of NiFe layers.