ATTOSCOPE · Measuring attosecond electron dynamics in molecules

The goal of the present proposal is to realize measurements of electronic dynamics in polyatomicmolecules with attosecond temporal resolution (1 as = 10^-18s). We propose to study electronicrearrangements following photoexcitation, charge migration in a molecular chain induced byionization and non-adiabatic multi-electron dynamics in an intense laser field. The grand questionaddressed by this research is the characterization of electron correlations which control the shape, properties and function of molecules. In all three proposed projects, a time-domain approach appears to be the most suitable since it reduces complex molecular dynamics to the purely electronic dynamics by exploiting the hierarchy of motional time scales. Experimentally, we propose to realize an innovative experimental setup. A few-cycle infrared (IR) pulse will be used to generate attosecond pulses in the extreme-ultraviolet (XUV) by high-harmonic generation. The IR pulse will be separated from the XUV by means of an innovative interferometer. Additionally, it will permit the introduction of a controlled attosecond delay between the two pulses. We propose to use the attosecond pulses as a tool to look inside individual IR- or UV-field cycles to better understand light-matter interactions. Time-resolved pump-probe experiments will be carried out on polyatomic molecules by detecting the energy and angular distribution of photoelectrons in a velocity-map imaging spectrometer. These experiments are expected to provide new insightsinto the dynamics of multi-electron systems along with new results for the validation andimprovement of theoretical models. Multi-electron dynamics is indeed a very complex subjecton its own and even more so in the presence of strong laser fields. The proposed experimentsdirectly address theses challenges and are expected to provide new insights that will be beneficial to a wide range of scientific research areas.""