Hot-electron dynamics at noble metal surfaces

The dynamics of excited electronic states at Ag surfaces is studied by evaluating the quasiparticle selfenergy within the GW approximation. The screened Coulomb interaction W is shown to be sensitive to the spatial variation of s-d screening near the surface. In the region of s-electron spill-out electronic damping is stronger than in the bulk due to the reduced s-d polarization, giving rise to shorter surface-state lifetimes. The lifetime of Ag image states is expected to be strongly reduced due to decay into surface plasmons.