Quantum-Well Wavefunction Localization and the Electron-Phonon Interaction in Thin Ag Nanofilms

TL;DR

This study investigates how quantum-well wavefunction localization affects electron-phonon interactions in thin silver nanofilms, revealing oscillations in coupling related to wavefunction localization rather than Fermi-level crossings.

Contribution

It uncovers a new mechanism linking wavefunction localization to electron-phonon coupling oscillations in thin metallic films.

Findings

Oscillations in electron-phonon coupling depend on film thickness.

Wavefunction localization influences electron-phonon interaction.

A new mechanism differs from Fermi-level crossing effects.

Abstract

The electron-phonon interaction in thin Ag-nanofilms epitaxially grown on Cu(111) is investigated by temperature-dependent and angle-resolved photoemission from silver quantum-well states. Clear oscillations in the electron-phonon coupling parameter as a function of the silver film thickness are observed. Different from other thin film systems where quantum oscillations are related to the Fermi-level crossing of quantum-well states, we can identify a new mechanism behind these oscillations, based on the wavefunction localization of the quantum-well states in the film.