Phys Rev Lett. 2014 Jan 17;112(2):023602. doi: 10.1103/PhysRevLett.112.023602. Epub 2014 Jan 14.

Attosecond time-resolved photoelectron dispersion and photoemission time delays.

Physical review letters

Q Liao, U Thumm

PMID: 24484011 DOI: 10.1103/PhysRevLett.112.023602

Abstract

We compute spectrograms and relative time delays for laser-assisted photoemission by single attosecond extreme ultraviolet pulses from valence band (VB) and 2p core levels (CLs) of a Mg(0001) surface within a quantum-mechanical model. Comparing the time-dependent dispersion of photoelectron (PE) wave packets for VB and CL emission, we find striking differences in their dependence on the (i) electron mean free path (MFP) in the solid, (ii) screening of the streaking laser field, and (iii) chirp of the attosecond pulse. The relative photoemission delay between VB and 2p PEs is shown to be sensitive to the electron MFP and screening of the streaking laser field inside the solid. Our model is able to reproduce a recent attosecond-streaking experiment [S. Neppl et al., Phys. Rev. Lett. 109, 087401 (2012)], which reveals no relative streaking time delay between VB and 2p PEs.

Publication Types

• Journal Article