Hannover 2003 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
A: Atomphysik
A 16: Multiphotonprozesse 2
A 16.6: Vortrag
Donnerstag, 27. März 2003, 15:15–15:30, F128
Quantum-orbit analysis of nonsequential double ionization — •C. Figueira de Morisson Faria1, H. Schomerus2, and W. Becker1 — 1Max-Born-Institut, 12489 Berlin — 2Max-Planck-Institut für Physik komplexer Systeme, 01187 Dresden
According to the rescattering mechanism, high-order
above-threshold ionization and nonsequential double ionization
(NSDI)
occur via elastic or inelastic collision, respectively, of
an electron with its parent ion in the presence of a strong
laser field.
For these processes, via a saddle-point evaluation the
quantum-mechanical
S matrix can be expanded in
terms of complex orbits that describe these electrons.
This No-dqquantum-orbitNo-dq formalism [1] is computationally
powerful and provides,
at the same time, physical insight and predictive power.
The orbits naturally
come in pairs, which coalesce near the classical cutoffs.
This causes
problems with the saddle-point approximation, which are
overcome by the
so-called uniform
approximation. In principle, arbitrary potentials can be
employed for
binding and rescattering [2]. New applications are presented
for NSDI that
concentrate
on the role of the binding and rescattering potentials,
electron-electron repulsion in the final state, and the
contributions of
"slow-downNo-dq versus "speed-upNo-dq collisions.
[1] P. Salieres et al., Science 292, 902 (2001). [2] C. Figueira de Morisson Faria, H. Schomerus, and W. Becker, Phys. Rev. A 66, 043413 (2002); C. Figueira de Morisson Faria and W. Becker, Laser Phys. (in press) (2003).