Berlin 2014 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MO: Fachverband Molekülphysik
MO 16: Atomic clusters (with A)
MO 16.7: Vortrag
Donnerstag, 20. März 2014, 12:15–12:30, BEBEL E44/46
Real-time observation of recombination in clusters exposed to intense HHG pulses — •Bernd Schütte1, Mathias Arbeiter2, Thomas Fennel2, Filippo Campi3, Marc J. J. Vrakking1, and Arnaud Rouzée1 — 1Max-Born-Institut, Berlin, Germany — 2Universität Rostock, Germany — 3Lund University, Sweden
High-order harmonic generation (HHG) sources provide light pulses in the extreme-ultraviolet (XUV) spectral range with unique properties including a large wavelength tunability, extremely short pulses down to the attosecond range and a straightforward manner in which pump-probe measurements can be performed. Here we demonstrate that the advantageous features of HHG in combination with the velocity map imaging (VMI) technique lead to a significant improvement in the understanding of cluster dynamics.
The observation of very low kinetic energy electrons from rare-gas clusters exposed to intense HHG pulses is attributed to electron-ion recombination processes to Rydberg states in the expanding nanoplasma. Their subsequent reionization with the DC detector electric field known as frustrated recombination is observed experimentally for the first time. Moreover, using a time-delayed visible or infrared pulse, we investigate the recombination dynamics of quasifree electrons to atomic excited states during the nanoplasma expansion, a method termed reionization of excited atoms from recombination (REAR). In addition, we show that REAR can be used as a sensitive probe for tracing the cluster expansion up to the nanosecond range.