Hong, I.-PoBrun, ChristophePatthey, FrancoisSklyadneva, I. Yu.Zubizarreta, X.Heid, R.Silkin, V. M.Echenique, P. M.Bohnen, K. P.Chulkov, E. V.Schneider, Wolf-Dieter2010-11-302010-11-302010-11-30200910.1103/PhysRevB.80.081409https://infoscience.epfl.ch/handle/20.500.14299/59893WOS:000269639300029Using low-temperature scanning tunneling spectroscopy at 5 and 50 K, we studied the linewidth of unoccupied quantum-well states in ultrathin Pb islands, grown on Si(111) on two different Pb/Si interfaces. A quantitative analysis of the differential conductance spectra allowed us to determine the electron-electron (e-e), electron-phonon (e-ph) and the interface and defect contributions to the lifetime. Layer-dependent ab initio calculations of the e-ph linewidth contribution are in excellent agreement with the data. Importantly, the sum of the calculated e-e and e-ph lifetime broadening follows the experimentally observed quadratic energy dependence.ab initio calculationselectron-phonon interactionselemental semiconductorsleadmetallic thin filmsquantum wellsscanning tunnelling spectroscopysiliconspectral line broadeningSurfaceFilmsMicroscopeLifetimeDecay mechanisms of excited electrons in quantum-well states of ultrathin Pb islands grown on Si(111): Scanning tunneling spectroscopy and theorytext::journal::journal article::research article