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A method for detecting dc spin current propagation through an epitaxial antiferromagnetic (AFM) NiO layer is presented. Spin current is generated by spin pumping from an adjoining ferromagnetic (FM) layer and detected in a non-magnetic metallic layer by the inverse spin Hall effect. Comparison is made with a YIG/Pt bilayer, where only the Pt layer is electrically conducting, but for which spin Hall magnetoresistance makes an additional contribution to the measured signal. The signal obtained from the multilayered stack containing the AFM NiO layer is found to contain additional contributions due to anisotropic magnetoresistance. By exciting the sample with out-of-plane rf magnetic field and making measurements with a static field applied at different orientations within the plane of the sample, a signal associated with the dc spin current may be identified. [ABSTRACT FROM AUTHOR]

The magnetic properties of exchange biased systems deposited on top of fullerene-based materials have been studied. An enhanced exchange bias field has been observed for Si/SiO2/C60/Co/Cu/Co/IrMn/Ta and Si/SiO2/FeC60/Co/Cu/Co/IrMn/Ta in comparison to a typical structure of Si/SiO2/Ta/Co/Cu/Co/IrMn/Ta. Here the magnetic properties of the devices are changed significantly with an organic underlayer or seed layer. The magnetic ordering is well maintained, and C60 seeding results in an exchange bias of (19.5 \pm 0.5) mT, some 7 mT higher than that of Ta seeded spin valves (12.5 \pm 0.5 mT). A combination of MOKE (magneto-optical Kerr effect), X-ray diffraction and Raman spectroscopy have been used to characterize the materials and further understand the interactions between the Co and fullerene-based materials. [ABSTRACT FROM AUTHOR]