Femtosecond measurements of surface-state-electron dynamics on nanostructured Ni surfaces

Summary form only given. We will describe our fs, two-photon photoemission measurements of electron lifetimes and dispersion curves on regular arrays of /spl sim/16 /spl Aring/ wide Ni steps, decorated with monolayer stripes of Ag. The experiments have measured the lifetimes and dispersive properties of the occupied surface and normally unoccupied image electron states. For the first time, we observed band-folding of an induced surface state with a controllable bandwidth.