WE-Heraeus-Seminar — Ultrafast Science and Data of Electronic Processes: From Attosecond Time Scales to Intense X‐ray Interactions

The Nobel Prize in Physics 2023, awarded for the generation of attosecond light pulses, showcasts the scientific success and the impact of the shortest flashes of light that can be generated. First pathfinder experiments were conducted throughout the last two decades, mostly based on the "traditional" attosecond-pulse generation method by high-order harmonic generation, now implemented in many research laboratories around the world. Since a few years, an orthogonal access to attosecond science is emerging at large-scale electron-accelerator facilities: Attosecond pulses at X-ray free-electron lasers (XFELs). These new developments give rise to an entire new field: Nonlinear x-ray science and its applications in fundamental research. Ultrashort x-ray pulses offer a novel view on the time-dependent electronic structure of matter, by harnessing spectroscopic and structural imaging techniques. An emerging frontier in the field is acquiring, processing, and analysing the large data streams from a multitude of light-source parameters and ever more sophisticated detectors, delivering multi-dimensional data arrays from which quantitative and qualitatively new information needs to be extracted and interpreted, to ultimately extract information to observe physical processes on atomic length- and electronic timescales.