Many-body Effects in Angle-resolved Photoemission: Quasiparticle Energy and Lifetime of a Mo(110) Surface State

TL;DR

This study investigates many-body effects influencing the quasiparticle energy and lifetime of a Mo(110) surface state using high-resolution photoemission, revealing electron-phonon interactions and defect scattering impacts.

Contribution

It provides the first observation of electron-phonon induced mass enhancement and rapid lifetime changes near the Fermi level in Mo(110).

Findings

Electron-phonon coupling affects quasiparticle mass and lifetime.

Defects contribute to quasiparticle scattering and broadening.

Rapid changes in lifetime occur near the Fermi level.

Abstract

In a high-resolution photoemission study of a Mo(110) surface state various contributions to the measured width and energy of the quasiparticle peak are investigated. Electron-phonon coupling, electron-electron interactions and scattering from defects are all identified mechanisms responsible for the finite lifetime of a valence photo-hole. The electron-phonon induced mass enhancement and rapid change of the photo-hole lifetime near the Fermi level are observed for the first time.