화학공학소재연구정보센터
Applied Surface Science, Vol.169, 68-72, 2001
Theory of time-resolved two-photon photoemission from Cu(111): effect of Coulomb interactions among electrons
The effect of Coulomb interactions among electrons on the time-resolved two-photon photoemission spectra of Cu(1 1 1) is investigated by nonequilibrium perturbation theory. It is demonstrated that then are contributions to photoemission via an image state on the surface from processes involving scattering of photoexcited electrons and holes due to Coulomb interactions. As a result, the con-elation trace (photoelectron intensity as a function of the pump-probe delay time) is affected by the lifetimes of the electron in the image stale, the photoexcited electron and hole.