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Title: Quantum beat oscillations in the two-color-photoionization continuum of neon and their dependence on the intensity of the ionizing laser pulse

Journal Article · · Physical Review. A
; ; ;  [1]
  1. Max-Born-Institut fuer Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2 A, D-12489 Berlin (Germany)

We investigate quantum beat oscillations in the photoionization continuum of Ne atoms that are photoionized by absorption of two photons via a group of excited bound states using ultrashort extreme ultraviolet and infrared laser pulses. The extreme ultraviolet pulse starts an excited-state wave packet that is photoionized by a high-intensity infrared pulse after a variable time delay. We analyze the continuum quantum beats from this two-step photoionization process and their dependence on the photoelectron kinetic energy. We find a pronounced dependence of the quantum beat amplitudes on the photoelectron kinetic energy. The dependence changes significantly with the applied infrared laser-pulse intensity. The experimental results are in good qualitative agreement with a model calculation that is adapted to the experimental situation. It accounts for the intensity dependence of the quantum beat structure through the coupling of the excited-state wave packet to other bound Ne states induced by the high-intensity infrared laser pulse.

OSTI ID:
22068743
Journal Information:
Physical Review. A, Vol. 84, Issue 3; Other Information: (c) 2011 American Institute of Physics; Country of input: Syrian Arab Republic; ISSN 1050-2947
Country of Publication:
United States
Language:
English