Epitaxial Co-Au superlattices.
We demonstrate the growth of epitaxially ordered Co-Au superlattices by ultrahigh-vacuum deposition techniques. The superlattice structure consists of hcp Co(0001) and fcc Au(111) layers with the in-plane Co [$11\overline{2}0$] crystallographic axis parallel to GaAs [001]. X-ray scattering, high-resolution transmission-electron microscopy, and measurements of the magnetic anisotropy show that the Co-Au interfaces are abrupt even in the presence of a large lattice mismatch.