Asymmetries in strong-field photoionization by few-cycle laser pulses: Kinetic-energy spectra and semiclassical explanation of the asymmetries of fast and slow electrons

Journal Article · Sun May 15 04:00:00 EDT 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.71.053815· OSTI ID:20717816

Chelkowski, Szczepan; Bandrauk, Andre D ^[1]

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1. Laboratoire de Chimie Theorique, Faculte des Sciences, Universite de Sherbrooke, Quebec, J1K 2R1 (Canada)

Using numerical solutions of a time-dependent Schroedinger equation for a hydrogen atom in a linearly polarized few-cycle laser field, we calculate the left-right photoelectron kinetic-energy spectra measured by two opposing detectors placed along the laser polarization vector, with laser focus in the center. The fastest electrons show huge asymmetries strongly dependent on the laser carrier-envelope (CE) phase which confirms the recent theoretical results [D. B. Milosevic et al., Opt. Express 11, 1418 (2003)], obtained from a modified strong field approximation model which includes rescattering by the Coulomb potential. This asymmetry can also be explained by a simple semiclassical model in which the electron after tunneling through a potential barrier returns to the proton and is elastically backscattered in the presence of the laser field thus acquiring energy close 10U{sub p} where U{sub p} is the electron ponderomotive energy in the laser field. We also present a semiclassical interpretation of counterintuitive left-right asymmetries of slow electrons discussed in our previous work [Phys. Rev. A. 70, 013815 (2004)]. Our analysis shows that the Coulomb attraction from the proton must be included in the standard tunneling model in order to account for the CE phase dependent angular asymmetry seen in our previous numerical calculations.

• OSTI ID: 20717816
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 5 Vol. 71; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ASYMMETRY
ATOMS
COULOMB FIELD
ELECTRONS
HYDROGEN
KINETIC ENERGY
LASER RADIATION
NUMERICAL SOLUTION
PHOTOELECTRON SPECTROSCOPY
PHOTOIONIZATION
PHOTON-ATOM COLLISIONS
POLARIZATION
PONDEROMOTIVE FORCE
POTENTIAL ENERGY
PROTONS
PULSES
RESCATTERING
SCHROEDINGER EQUATION
SEMICLASSICAL APPROXIMATION
TIME DEPENDENCE
TUNNEL EFFECT