Femtosecond two-photon photoemission studies of image-potential states

High-resolution two-photon photoemission studies with femtosecond time resolution permit the accurate determination of decay and dephasing processes for image-potential states. The influence of adsorbates on the respective inelastic and quasielastic scattering processes is investigated for Cu on Cu(100) and Cu(111). The results are discussed in relation to previous work for CO on Cu(100). (C) 2000 Elsevier Science B.V. All rights reserved.