Spin polarized neutron scattering study of NiCo/Cu multilayers

Spin polarized neutron reflectometry measurements were performed on Ni80Co20/Cu multilayers with a Cu spacer thickness of 20 Å, corresponding to the second oscillation peak in the magnetoresistance of the NiCo/Cu multilayer system. Measurements in a 15 Oe field indicate a nearly perfect antiferromagnetic stacking of the magnetic moments in successive Ni80Co20 layers. The existence of a small magnetic anisotropy in these magnetically soft multilayers leads to the canting of the magnetic moments at an angle of ∼70° with respect to the neutron spin polarization. This interlayer antiferromagnetic coupling can be suppressed by an applied field of ∼200 Oe.