Nonadiabatic dynamics of electron scattering from adsorbates in surface bands

Scientific paper - Original scientific paper

• Author: Branko Gumhalter
• Author: Antonio Šiber
• Author: Hrvoje Buljan
• Author: Thomas Fauster
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

We present a comparative study of nonadiabatic dynamics of electron scattering in quasi-two-dimensional surface band which is induced by the long-range component of the interactions with a random array of adsorbates. Using three complementary model descriptions of intraband spatiotemporal propagation of quasiparticles that go beyond the single-adsorbate scattering approach we are able to identify distinct subsequent regimes of evolution of an electron following its promotion into an unoccupied band state: (i) early quadratic or ballistic decay of the initial-state survival probability within the Heisenberg uncertainty window, (ii) preasymptotic exponential decay governed by the self-consistent Fermi golden rule scattering rate, and (iii) asymptotic decay described by a combined inverse power-law and logarithmic behavior. The developed models are applied to discuss the dynamics of intraband adsorbate-induced scattering of hot electrons excited into the n=1 image-potential band on Cu(100) surface during the first stage of a two-photon photoemission process. Estimates of crossovers between the distinct evolution regimes enable assessments of the lifespan of a standard quasiparticle behavior and thereby of the range of applicability of the widely used Fermi golden rule and optical Bloch equations approach for description of adsorbate-induced quasiparticle decay and dephasing in ultrafast experiments.

• Keywords (english): quantum dynamics; scattering; adsorbates; impurities; surfaces; non-adiabatic
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical review B: Condensed matter and materials physics
• Numbering: vol. 78, no. 15, 155410
• p-ISSN: 1098-0121
• e-ISSN: 1550-235X
• DOI: https://doi.org/10.1103/PhysRevB.78.155410
• URN:NBN: urn:nbn:hr:217:114620
• Publication: 2008
• Document URL: http://link.aps.org/doi/10.1103/PhysRevB.78.155410
• Type of resource: Text
• Access conditions: Open access
• Public note: Copyright (2008) by the American Physical Society. Received 5 June 2008; published 9 October 2008.
• Created on: 2019-10-19 18:45:40