Aufsatz in einer Fachzeitschrift
Photoemission studies of the W(110)/Ag interface
Details zur Publikation
Autor(inn)en: | Feydt, J.; Elbe, A.; Engelhard, H.; Meister, G.; Goldmann, A. |
Publikationsjahr: | 2000 |
Zeitschrift: | Surface Science |
Seitenbereich: | 33-43 |
Jahrgang/Band : | 452 |
ISSN: | 0039-6028 |
Zusammenfassung, Abstract
We have taken normal emission photoelectron spectra using tunable synchrotron radiation from Ag overlayers grown epitaxially on W(110). One ordered monolayer (ML) exhibits four Ag-induced essentially d-like states at initial energies between 4 and 7 eV below E-F. Analysis of their intensity versus photon energy gives an interpretation in terms of d-like quantum well states at E-i=(-4.2+/-0.1)eV, (-4.6+/-0.1)eV and (-5.0+/-0.1)eV and a state at E-i=(-6.2+/-0.2)eV which couples strongly to a substrate bulk band. Quantum well states showing s-like character are identified at E-i=(-3.1+/-0.1)eV, related to an Ag thickness of 2 ML, and at E-i=(-2.4+/-0.1)eV, identified with the 3 ML film. Moreover, a d-like interface state is clearly identified at E-i =(-1.4+/-0.1)eV. Besides overlayer-induced attenuation, the substrate emission appears unchanged. All photoemission features observed in our study can be uniquely identified, and this gives a solid starting point for future adsorbate studies on W(110) covered with 1 or 2 ML Ag. (C) 2000 Elsevier Science B.V. All rights reserved.
We have taken normal emission photoelectron spectra using tunable synchrotron radiation from Ag overlayers grown epitaxially on W(110). One ordered monolayer (ML) exhibits four Ag-induced essentially d-like states at initial energies between 4 and 7 eV below E-F. Analysis of their intensity versus photon energy gives an interpretation in terms of d-like quantum well states at E-i=(-4.2+/-0.1)eV, (-4.6+/-0.1)eV and (-5.0+/-0.1)eV and a state at E-i=(-6.2+/-0.2)eV which couples strongly to a substrate bulk band. Quantum well states showing s-like character are identified at E-i=(-3.1+/-0.1)eV, related to an Ag thickness of 2 ML, and at E-i=(-2.4+/-0.1)eV, identified with the 3 ML film. Moreover, a d-like interface state is clearly identified at E-i =(-1.4+/-0.1)eV. Besides overlayer-induced attenuation, the substrate emission appears unchanged. All photoemission features observed in our study can be uniquely identified, and this gives a solid starting point for future adsorbate studies on W(110) covered with 1 or 2 ML Ag. (C) 2000 Elsevier Science B.V. All rights reserved.
