"Attosecond–resolved quantum dynamics: Opportunities and challenges."

"With the advent of sub-femtosecond ultrashort XUV pulses and of phase-stabilized IR pulses with sub-cycle time resolution, novel pathways have been opened up for studying time-resolved electronic quantum dynamics on the attosecond scale. These experiments pose challenges for theory: How do short pulses interact with matter? Which novel information can be extracted from time-resolved spectroscopies? In this talk, these issues will be addressed with the help of a few examples. One is the notion of time delay as physical observable. We show that the Eisenbud-Wigner-Smith time delay for atomic photoionization can now be determined by streaking or RABBITT with single-digit attosecond precision, however only when long-range interaction and IR field corrections are accounted for. For the more complex systems of a solid surface, time-resolved information on decohering processes such as electron transport or plasmon excitation can be extracted."