Temperature dependence of the magnetoresistance in Co/Re superlattices on Al₂O₃ (112^-0)

Using a patterned hcp [Co (17 Å)/Re (7Å)]₂₀ antiferromagnetically coupled superlattice, with the c axis in the film plane, magnetoresistance (MR) measurements were made in the temperature range between 5 K and room temperature. The MR was simulated and decomposed into its anisotropic magnetoresistance (AMR) and giant magnetoresistance (GMR) components using the magnetization as a function of angle determined from neutron reflectivity experiments. We find that the GMR is anisotropic and has a different temperature dependence than the AMR when I ⊥c and a similar dependence when I||c, where I is the applied current. This implies that interface spin-dependent scattering plays a more significant role when I ⊥c than when I||c.