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AMPD: EPS AMPD
AMPD 10: Sitzung 10
AMPD 10.1: Vortrag
Freitag, 6. April 2001, 09:55–10:30, H104
Collisions of Highly Charged Ions with Metal Clusters — •C. Guet1 and J. Daligault2 — 1Département de Physique Théorique et Appliquée CEA-Ile de France BP 12, 91680 Bruyères le Châtel Cedex, France — 2Département de Recherche Fondamentale sur la Matière Condensée CEA-Grenoble 17, rue des Martyrs, 38054 Grenoble Cedex 9, France
In peripheral collisions of highly charged ions with metal clusters electrons experience large amplitude motions which lead to multiple ionization and excitation. Both the residual charge excess and the coupling of the electronic excitation to the ionic motion results in the development of Coulomb instabilities in an as yet unexplored regime, see Ref[1].
This talk will present a theoretical model that allows to describe the hyghly non–linear dynamics of electrons and ions during and after a collision between a highly charged ion and a cluster of from a few ten up to several hundred alkali–metal atoms. The model is based on the self consistent mean field Vlasov equation for the delocalized electrons, and classical motion for the ions. The semiclassical Vlasov approach has been tested to be an excellent approximation to a purely quantal treatment, see Ref[2]. Once the validity of the semiclassical approximation is established, the Vlasov approach is superior to the quantal treatment in such respects that it can cope with more realistic ion potentials, with much larger systems, and with much longer simulation times. Typical simulation times are of the order of several hundred fs, which allows one to probe the response of the ions to the sudden loss of electrons. We shall emphasize how this response is quite different to that observed during and after irradiation by a fs intense laser pulse.
[1] F. Chandezon et al, Phys. Rev. Lett. 74, 3784, (1995); C. Guet et al, Z. Phys. D 40, 317 (1997); T. Bergen et al in "Similarities and Differences between Atomic Nuclei and Microclusters", AIP-416, 148 (1998).
[2] L. Plagne et al, Phys. Rev. A 61, 033201 (2000).