One-dimensional Ag-Cu superlattices on vicinal Cu(111)

Regular arrays of one-dimensional Ag stripes can be grown by adsorption and annealing of Ag on vicinal Cu(III). The Ag adlayer induces a periodic hill-and-valley nanostructure with alternating A,-covered (112)oriented facets and clean Cu stepped areas. The superlattice has been studied as a function of Ag coverage using a wedge (0.34-0.52 monolayers). The width of the Ag stripes is constant across the wedge (approximate to 45 Angstrom), such that the wavelength of the hill-and-valley structure varies from 140 Angstrom to 90 Angstrom and the width and step density of the Cu stepped areas is reduced accordingly. The structure of the Ag-covered stripes is consistent with a rotated, uniaxially compressed, close-packed layer that wets the Cu(112) plane.