The role of surface plasmons in the decay of image-potential states on silver surfaces

TL;DR

This paper investigates how surface plasmons influence the decay of image-potential states on silver surfaces, revealing that complex electron interactions lead to longer lifetimes than previously predicted, aligning theory with experiment.

Contribution

It demonstrates that the interplay of surface plasmons and non-local electron interactions explains the longer observed lifetimes of image states on Ag surfaces.

Findings

Surface plasmons do not shorten image-state lifetimes as previously thought.

Non-local electron interactions significantly affect decay processes.

Theoretical predictions now match experimental measurements.

Abstract

The combined effect of single-particle and collective surface excitations in the decay of image-potential states on Ag surfaces is investigated, and the origin of the long-standing discrepancy between experimental measurements and previous theoretical predictions for the lifetime of these states is elucidated. Although surface-plasmon excitation had been expected to reduce the image-state lifetime, we demonstrate that the subtle combination of the spatial variation of s-d polarization in Ag and the characteristic non-locality of many-electron interactions near the surface yields surprisingly long image-state lifetimes, in agreement with experiment.