Role of occupied d bands in the dynamics of excited electrons and holes in Ag

TL;DR

This paper investigates how occupied d bands influence the inelastic lifetimes of excited electrons and holes in silver, showing that including d electron screening improves agreement with experimental data.

Contribution

It introduces a model that incorporates occupied d bands as a polarizable background, enhancing the accuracy of lifetime predictions for bulk and surface states in Ag.

Findings

Inelastic lifetimes of bulk electrons match first-principles calculations.

Surface-state lifetime predictions align better with experiments when d electron screening is included.

Accounting for d bands improves understanding of electron dynamics in silver.

Abstract

The role that occupied $d$ bands play in the inelastic lifetime of bulk and surface states in Ag is investigated from the knowledge of the quasiparticle self-energy. In the case of bulk electrons, $sp$ bands are taken to be free-electron like. For surface states, the surface band structure of $sp$ states is described with the use of a realistic one-dimensional hamiltonian. The presence of occupied $d$ states is considered in both cases by introducing a polarizable background. We obtain inelastic lifetimes of bulk electrons that are in good agreement with first-principles band-structure calculations. Our surface-state lifetime calculations indicate that the agreement with measured lifetimes of both crystal-induced and image-potential induced surface states on Ag(100) and Ag(111) is considerably improved when the screening of $d$ electrons is taken into account.