M. Kübel,
K. J. Betsch,
N. G. Kling,
A. S. Alnaser,
J. Schmidt,
U. Kleineberg,
Y. Deng,
I. Ben-Itzhak,
G.G. Paulus,
T. Pfeifer,
J. Ullrich,
R. Moshammer,
M. F. Kling,
and B. Bergues
Non-sequential double ionization of Ar: from the single- to the many-cycle regime
New J. Phys., 16 :033008 (March 2014)
Non-sequential double ionization of Ar: from the single- to the many-cycle regime
New J. Phys., 16 :033008 (March 2014)
Abstract:
The transition from the near-single to the multi-cycle regime in non-sequential double ionization of argon is investigated experimentally. Argon atoms are exposed to intense laser pulses with a center wavelength around 790 nm and the momenta of electrons and ions generated in the double ionization process are measured in coincidence using a reaction microscope. The duration of the near transform-limited pulses is varied from 4 to 30 fs. We observe an abrupt collapse of the cross-shaped two-electron momentum distribution [17] in the few-cycle regime. The transition to longer pulses is further accompanied by a strong increase in the fraction of anti-correlated to correlated electrons.