https://doi.org/10.1140/epjd/e2005-00049-1
Coherent control calculations for helium atom in short and intensive XUV laser pulses
Institute for Theoretical Physics, Vienna University of Technology,
Wiedner Hauptstr. 8-10, 1040 Vienna, Austria
Corresponding author: a barna@concord.itp.tuwien.ac.at
Received:
24
September
2004
Revised:
17
March
2005
Published online:
26
April
2005
Coherent control calculations are presented for helium.
With the help of a genetic algorithm (GA) phase-modulated extreme
ultra violet (XUV) laser pulses were controlled to
maximize or minimize the non-resonant two-photon 
excitation.
Linearly polarized laser pulses were chosen at the frequency of 0.4 a.u.
with a duration of about 15 fs and 1014 Wcm-2 peak intensity.
We verified the theory that an antisymmetric spectral phase
around the two-photon resonance frequency maximizes the transition
probability.
Dark pulses which do not excite the system at all have however
symmetric spectral
phases around the two-photon resonance frequency.
PACS: 32.80.Wr – Other multiphoton processes / 32.80.Qk – Coherent control of atomic interactions with photons / 31.15.Ar – Ab initio calculations
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005
