Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

A: Fachverband Atomphysik

A 24: Interaction with Strong or Short Laser Pulses III (joint session A/MO)

A 24.2: Vortrag

Donnerstag, 9. März 2023, 15:00–15:15, F107

Free electron vortices in multiphoton ionization of molecules — •Darius Köhnke, Cornelia Opp, Tim Bayer, and Matthias Wollenhaupt — Carl von Ossietzky university Oldenburg, Institute of Physics, Germany

Since their theoretical proposal [1] and their first experimental demonstration [2], free electron vortices have attracted significant attention. So far, most of the theoretical and all of the experimental investigations were performed on atoms. Here, we present the first experimental demonstration of free electron vortices by multiphoton ionization (MPI) of molecules. Specifically, we study the creation of molecular vortices on C60 fullerenes using counter rotating circularly polarized femtosecond laser pulse sequences generated from a white-light supercontinuum. Since the discovery of the C60 molecule it has served as a benchmark system to study photo-induced dynamics in complex systems. Due to its high symmetry, the C60 molecule, is an ideal system to bridge the gap between atoms and more complex systems such as polyatomic molecules and clusters. It has been shown that C60 exhibits distinct atom-like electronic orbitals, termed superatomic molecular orbitals (SAMOS) [3], which play an important role in the MPI of fullerenes. By tomographic reconstruction of the three-dimensional photoelectron momentum distribution, we show that ionization from a SAMO with the polarization-tailored laser field creates a six-armed free electron vortex. [1] J. M. Ngoko Djiokap et. al, Phys. Rev. Lett., 115(11), 2015 [2] D. Pengel et. al, Phys. Rev. Lett., 118(5), 2017 [3] M. Feng et. al, Science, 320(5874), 2008