Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
A: Fachverband Atomphysik
A 36: Quantum dynamics in tailored waveforms
A 36.3: Hauptvortrag
Freitag, 15. März 2019, 11:30–12:00, S HS 3 Physik
Simple and robust control of resonant few-photon ionization — •Ulf Saalmann — MPI for the Physics of Complex Systems
It is shown that resonant few-photon ionization can be easily controlled by means of chirped laser pulses. Simply by changing the chirp direction one can switch between excitation and ionization with very high contrast [U Saalmann, S Kumar Giri and J M Rost, PRL 121 (2018) 153203], as calculated paradigmatically for the two-photon ionization of helium. This is a surprising consequence if rapid adiabatic passage is extended to include transitions to the continuum. The chirp phase-locks the linear combination of two resonantly-coupled bound states, whose ionization amplitudes interfere constructively or destructively depending on the chirp direction under suitable conditions. The phenomenon is illustrated by means of a minimal model.