Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

O: Oberflächenphysik

O 11: Elektronische Struktur (II)

O 11.2: Vortrag

Montag, 11. März 2002, 15:30–15:45, H44

Quantum-Size Effects in Ultrathin Ag Films on V(001): Electronic Structure and Photoelectron Spectroscopy — •Arthur Ernst and Jürgen Henk — MPI für Mikrostrukturphysik, Halle (Saale)

Experimental photoemission investigations [1] of ultrathin Ag films deposited on V(001) reported that manifestations of quantum-size effects in the spectra could not be explained by model calculations. These findings question the relevance of the latter, which, however, successfully describe photoemission from prototypical systems (e. g., Co/Cu) [2].

To resolve the origins of this apparent discrepancy, we performed first-principles calculations for several Ag/V systems (bulk, surfaces, interfaces, and thin films). Quantum-well states in the Ag films show the typical dispersion with film thickness, but their spectral densities behave different than expected. This feature can be traced back to band-structure effects and hybridization between Ag and V states.

Quantization effects in the theoretical spectra, in particular the pronounced intensity oscillations in the constant-initial-state mode, are discussed with respect to the spectral densities and compared to experiment.

[1] T. Valla, P. Pervan, M. Milun, A. B. Hayden, and D. P. Woodruff, Phys. Rev. B 54 (1996) 11 786.

[2] J. Henk and B. Johansson, J. Elec.  Spec. 105 (1999) 187.