ABSENCE OF FERROMAGNETISM IN EPITAXIAL-FILMS OF ULTRATHIN PD, RH, AND RH ON PD GROWN ON AU(100)

In situ longitudinal and polar Kerr-effect measurements were used to search for ferromagnetism in films of Pd/Au(100), Rh/Au(100), and Rh/Pd/Au(100) with overlayer thicknesses of 0.5-5 monolayers (ML). No evidence for ferromagnetism was found in these systems above 100 K and for applied magnetic fields up to 2.2 kOe. Based on our low-energy-electron-diffraction and Auger data, we find that all three systems grow epitaxially, and that there is layer-by-layer growth for Pd/Au(100) at 300 K, layer growth for Rh/Au(100) at 100 K up to 2 ML followed by island formation, and layer growth for Rh/Pd/Au(100) at 100 K.