Attosecond time-resolved streaked photoemission from Mg-covered W(110) surfaces
Date
2015-09-08
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Description
Citation: Liao, Q., & Thumm, U. (2015). Attosecond time-resolved streaked photoemission from Mg-covered W(110) surfaces. Physical Review A, 92(3), 6. doi:10.1103/PhysRevA.92.031401
We formulate a quantum-mechanical model for infrared-streaked photoelectron (PE) emission by ultrashort extreme ultraviolet (XUV) pulses from an adsorbate-covered metal surface, exposing the influence of microscopic PE dispersion in substrate and adsorbate on the interpretation of streaked photoemission spectra and photoemission time delays. We validate this numerical model first by reproducing measured relative photoemission delays (a) between valence-band and 2p-core-level (CL) PEs emitted from clean Mg(0001) surfaces and (b) between conduction-band (CB) and 4f -CL PEs from clean W(110) surfaces at two XUV-pulse central photon energies. Next, applying this model to ultrathin Mg adsorbate layers on W(110) substrates, we reproduce (i) the measured nonmonotonic dependence of relative photoemission delays between CB andMg(2p) PEs and (ii) the monotonic dependence of relative delays between W(4f) andMg(2p) PEs in a recent experiment
We formulate a quantum-mechanical model for infrared-streaked photoelectron (PE) emission by ultrashort extreme ultraviolet (XUV) pulses from an adsorbate-covered metal surface, exposing the influence of microscopic PE dispersion in substrate and adsorbate on the interpretation of streaked photoemission spectra and photoemission time delays. We validate this numerical model first by reproducing measured relative photoemission delays (a) between valence-band and 2p-core-level (CL) PEs emitted from clean Mg(0001) surfaces and (b) between conduction-band (CB) and 4f -CL PEs from clean W(110) surfaces at two XUV-pulse central photon energies. Next, applying this model to ultrathin Mg adsorbate layers on W(110) substrates, we reproduce (i) the measured nonmonotonic dependence of relative photoemission delays between CB andMg(2p) PEs and (ii) the monotonic dependence of relative delays between W(4f) andMg(2p) PEs in a recent experiment
Keywords
Image-Potential States, Work Function, Elements, Films, Optics, Physics