Speaker
Description
Progress in attosecond science in the past decade has enabled the study of ultrafast electronic
processes with unprecedented temporal resolution [1]. We extended an interferometric two-photon
technique named RABBITT [2] based on attosecond XUV pump pulses and a phase-matched IR probe
field from gas phase to solid surfaces to study the dynamics of the photoelectric effect [3].
Experiments on the noble metal surfaces Ag(111) and Au(111) revealed a strong energy
dependence of the delays for photoemission from the d-valence band [3]. The origin of photoemission
delays in solid surfaces has been the subject of numerous theoretical investigations and initial vs. final
state effects have been discussed heavily. Our experiments were sensitive for final state effects only
and will be discussed in terms of final state band structure and electron propagation.
Interpretation of the observed delays requires a precise model of the probe field distribution at the
surface. The RABBITT technique was used in a similar experiment to sample the IR field distribution
on a Cu(111) surface [4]. Finally, I will show how such techniques can be used to study the effective
field of low-frequency THz pulses at metal surfaces and nanostructures [5].
