Mainz 2017 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
A: Fachverband Atomphysik
A 26: Poster Session II
A 26.34: Poster
Mittwoch, 8. März 2017, 17:00–19:00, P OG1
Modification of Coulomb focusing of tunneled electrons in intense elliptically polarized mid-IR laser fields — •Jiří Daněk1, Karen Z. Hatsagortsyan1, Jochen Maurer2, Benjamin Willenberg2, Benedikt W. Mayer2, Christopher R. Phillips2, Lukas Gallmann2,3, Ursula Keller2, and Christoph H. Keitel1 — 1Max Planck Institute for Nuclear Physics, Heidelberg, Germany — 2Department of Physics, ETH Zurich, Switzerland — 3Institute of Applied Physics, University of Bern, Switzerland
Photoelectron momentum distributions (PMD) in the tunneling regime of ionization in an elliptically polarized laser field (3.4 µm) are investigated using classical-trajectory Monte-Carlo simulations. The signatures of the Coulomb field of the atomic core are identified and explained. In addition to the known Coulomb effect on the rotation of the PMD ellipse due to the Coulomb momentum transfer at the tunnel exit along the laser instantaneous polarization direction, we find the effect of the recollisions in the PMD at small values of the ellipticity. The recollisions are essentially modified in the elliptically polarized laser field, as the Coulomb focusing (CF) is very sensitive to all forces acting on the tunneled electrons. However, similarity of the CF in a linearly polarized case and in a case of a small ellitpicity can be found. The appearance and visibility of new features of PMD depend strongly on ellipticity and regimes can be identified where different features dominate. We focus on the theoretical analysis and investigate the PMD modifications analytically in the recollision picture, and present a qualitative analysis via the modified classical trajectories.