EXPERIMENTAL PHOTOHOLE LIFETIMES DERIVED FROM TWO-DIMENSIONAL STATES IN Ag(111) FILMS DEPOSITED ONTO H-PASSIVATED Si(111)-(1 × 1) SURFACES

Abstract

The linewidth of two-dimensional states appearing in the valence band spectra of 6–12-monolayer Ag(111) films deposited onto H-passivated Si (111)-(1 × 1) substrates has been analyzed in order to obtain a lower limit of the photohole lifetime. An inverse quadratic energy dependence is expected according to the Fermi liquid theory. However, in contrast with the observed in the literature for Ag single crystals, an inverse linear energy dependence has been found for the photohole lifetime. This discrepancy could be attributed to the quantization in the Γ-L direction of the Ag-sp states available for the hole decay, which does not fulfill the energy-independent density of states hypothesis of the Fermi liquid theory.