Attosecond imaging of molecular electronic wave-packets using XUV radiation

R. Taïeb
LCPMR, UPMC/CNRS, 11 rue Pierre et Marie Curie, 75231 Paris, France

The interaction of atomic or molecular gases with intense femtosecond
lasers revealed, since the mid 80's, much unexpected highly non-linear
phenomena. One of the most spectacular response of the gas is the
emission of coherent light bursts of sub-femtosecond duration, composed
of harmonics of the laser frequency over a wide spectrum. I will present
and analyze the tomographic imaging of of the molecular
wave functions of nitrogen, via a complete set of experimental data
consisting of harmonic amplitudes and phases. I will discuss the
validity and limitations of the model on which the method is based and
demonstrate that, under certain conditions, it allows to image the
molecule's HOMO as well as the closest lower orbital (HOMO-1). In
addition, combining the spatial and temporal aspects, I will show that
the wave-packet of the electronic hole left in the molecule after
ionization can be reconstructed with a temporal resolution of ± 300 as.