Coherent excitation of shake-up states in rare gas atoms by attosecond xuv pulses

In a recent experiment [2], Uiberacker et al. exposed neon atoms to a phase-stabilized fewcycle infrared (IR) laser field and a synchronized attosecond XUV pulse. The XUV pulse leads to single ionization of the Ne atom and the creation of excited (shake-up) states in the residual Ne ion. The IR pulse can then further ionize the Ne ion, thus serving as a probe for the quantum state of the singly ionized ion. By monitoring the yield of doubly charged Ne ions as a function of the time delay between the two pulses the (ionization) dynamics of the electronic wave packet created by the XUV pulse can thus be studied.