• DOI:10.1103/PhysRevA.95.063417
• Corpus ID: 119331745

Tracing transient charges in expanding clusters

@inproceedings{Schutte2016TracingTC,
  title={Tracing transient charges in expanding clusters},
  author={Bernd Schutte and Marc J. J. Vrakking and Arnaud Rouz'ee},
  year={2016}
}

• B. Schutte, M. Vrakking, A. Rouz'ee
• Published 15 December 2016
• Physics

We study transient charges formed in methane clusters following ionization by intense nearinfrared laser pulses. Cluster ionization by 400 fs (I = 1 × 10 W/cm) pulses is highly efficient, resulting in the observation of a dominant C ion contribution. The C ion yield is very small, but is strongly enhanced by applying a time-delayed weak near-infrared pulse. We conclude that most of the valence electrons are removed from their atoms during the laser-cluster interaction, and that electrons from the nanoplasma recombine with ions and populate Rydberg states when the cluster expands, leading to a decrease of the average charge state of individual ions. Furthermore, we find clear bound-state signatures in the electron kinetic energy spectrum, which we attribute to Auger decay taking place in expanding clusters. Such nonradiative processes lead to an increase of the final average ion charge state that is measured in experiments. Our results suggest that it is crucial to include both recombination and nonradiative decay processes for the understanding of recorded ion charge spectra.