Interlayer magnetic coupling in epitaxial Fe/Cr(211) and (100) superlattices

We present magnetic characterization of epitaxial Fe/Cr(211) and Fe/Cr(100) superlattices grown simultaneously on MgO(110) and (100) substrates, respectively. At room temperature, the coupling for these two orientations oscillates in sign with the same period (18Å), phase and strength. These results indicate that the long-period oscillation is independent of the nested feature of the Cr Fermi-surface. We examine the temperature dependence of interlayer coupling and find a uniform AF bias develops in the (211) samples upon cooling and observe strongly temperature-dependent biquadratic coupling in the (100) samples.