Time‐Resolved Two‐Photon Photoemission on Surfaces and Nanoparticles

Abstract Time‐resolved two‐photon photoemission spectroscopy allows an insight to be gained into ultrafast dynamic surface processes. In this chapter, we first discuss the relaxation dynamics of excited electrons and holes for metals, and also describe the behavior of excitonic states on bandgap materials which show lifetimes well into the microsecond regime. Electron transfer processes to adsorbates are discussed for typical examples. New approaches for photoelectron imaging with time resolution are presented which extend time‐resolved investigations to localized dynamics on nanoparticles. Lifetime maps allow to study exciting prospects of propagation dynamics of surface plasmon polaritons with subfemtosecond resolution. Phase‐ and polarization‐ controlled optical fields also open a new area of nanoscopic dynamic studies with subwavelength spatial and femtosecond time resolution.