Layer-by-layer-resolved quantum-well states in ultrathin silver islands on graphite: A photoemission study

Layer-resolved quantum-well states (QWS’s) corresponding to islands of different thicknesses for ultrathin Ag films on graphite have been observed by angle-resolved ultraviolet photoemission. The spectral linewidth dependence on island thickness and on binding energy is well described within a phase-accumulation model, taking into account the specific quantum-well barriers involved. Thus high-resolution photoemission of QWS’s provides an interesting tool to investigate the morphology and island-height distribution of ultrathin metal films.