Temperature dependence of the dynamics of the first image-potential state on Ag(111)

Abstract

The temperature dependence of the dynamics of electrons in the n=1 image potential state on the Ag(111) surface has been investigated by means of time-resolved two-photon photoemission spectroscopy and many-body calculations. We show that the decay rate of electrons in this state grows linearly with temperature. The thermal shortening of the lifetime is caused by the increase of the electron-electron scattering rate, due to deeper penetration of the image state wave function into the bulk metal at higher temperature. The electron-phonon scattering in this state is found to be small. © 2012 American Physical Society.