title: Simulating pump-probe photoelectron and absorption spectroscopy on the attosecond timescale with time-dependent density functional theory.
abstract: Molecular absorption and photoelectron spectra can be efficiently predicted with real-time time-dependent density functional theory. We show herein how these techniques can be easily extended to study time-resolved pump-probe experiments, in which a system response (absorption or electron emission) to a probe pulse is measured in an excited state. This simulation tool helps with the interpretation of fast-evolving attosecond time-resolved spectroscopic experiments, in which electronic motion must be followed at its natural timescale. We show how the extra degrees of freedom (pump-pulse duration, intensity, frequency, and time delay), which are absent in a conventional steady-state experiment, provide additional information about electronic structure and dynamics that improve characterization of a system. As an extension of this approach, time-dependent 2D spectroscopy can also be simulated, in principle, for large-scale structures and extended systems.
authors.affiliation: Nano-Bio Spectroscopy Group and ETSF Scientific Development Center, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018 San Sebastian, Spain. umberto.degiovannini@ehu.es
authors.forename: Umberto
authors.initials: U
authors.lastname: De Giovannini
authors.forename: Gustavo
authors.initials: G
authors.lastname: Brunetto
authors.forename: Alberto
authors.initials: A
authors.lastname: Castro
authors.forename: Jessica
authors.initials: J
authors.lastname: Walkenhorst
authors.forename: Angel
authors.initials: A
authors.lastname: Rubio
mesh_terms: D056951:Photoelectron Spectroscopy; D011789:Quantum Theory; D013997:Time Factors; D056928:X-Ray Absorption Spectroscopy