XUV and X-ray induced ultrafast electron dynamics in gas-phase targets*

We exploit the new capabilities of coherent light sources producing sub-femtosecond pulses to manipulate electronic dynamics in atoms and molecules with attosecond resolution. Attosecond pump-probe spectroscopy using high-order harmonic generation has made it possible to retrieve time-resolved images of molecular excitation and ionization processes [1-3], at the heart of electron and charge transfer reactions of multidisciplinary interest. Our most recent theoretical progresses on recent applications of these techniques on polyatomic molecules will be presented. Moreover, the high intensities and brilliance of light pulses produced in free-electron lasers (FELs) and X-ray FELs give access to a manifold of non-linear phenomena that have remained experimentally unexplored until now [4,5], e.g. highly coherent multiphoton ionization processes on small targets. We will discussed the interpretation and outcome of recent, and possible future, experiments at FELs with particular emphasis on non-linear processes strongly dominated by electron-electron and electron-nuclear correlations.

 

[1] H. Ahmadi et al., Nature Communications 13, 1242 (2022)

[2] J. Delgado et al., Faraday Discussions 228, 349 (2021)

[3] A. Palacios and F. Martín, WIREs: Comp. Molec. Science 10, e1430 (2020)

[4] A. Sopena, A. Palacios, F. Catoire, H. Bachau and F. Martín, Comm. Physics 4, 253 (2022)

[5] L. Varvarezos et al., J. Phys. Chem. Lett. 14, 24 (2023)