Temperature dependence of photoemission from quantum-well states in Ag/V(100): Moving surface-vacuum barrier effects - art. no. 085411

The temperature dependence of angle-resolved photoemission from quantum-wel l states in ultrathin films of Ag on V(100) has been examined for films fro m 1-8 ML thickness within the temperature range 45-600 K. Contrary to bulk solids, the photoemission peaks shift to higher binding energy as the tempe rature is increased. The temperature dependence of the peak widths is linea r, consistent with the expected behavior for electron-phonon coupling, but the coupling parameter lambda is found to show a strong oscillatory depende nce on film thickness, with some values many times larger than those found for bulk silver. The observations are explained in terms of the influence o n both the initial and final states in the photoemission process of the sta tic and dynamic movements of the surface-vacuum interface barrier induced b y temperature changes.