Semiclassical complex-time method for tunneling ionization: Molecular suppression and orientational dependence

Journal Article · Mon Mar 15 04:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.81.033417· OSTI ID:21408451

Gallup, Gordon A; Fabrikant, Ilya I ^[1]

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1. Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588-0111 (United States)

We apply a previously developed semiclassical complex time method to the calculation of tunneling ionization of several diatomic molecules and CO{sub 2}. We investigate the presence or absence of the molecular suppression effect by calculating ionization rates of N{sub 2} versus Ar, O{sub 2} versus Xe, F{sub 2} versus Ar, and CO versus Kr. Comparisons with other theories, including the molecular-orbital-Ammosov-Delone-Krainov (MO-ADK) model and the strong-field approximation, are given. We also analyze the dependence of the ionization rate on the angle {theta}{sub F} between the molecular axis and the field direction. The theoretical results agree quite well with experiment for N{sub 2} and O{sub 2} but give too low a value of the peak angle {theta}{sub F} for CO{sub 2}. Our calculations give small values of the ionization rates for O{sub 2} and CO{sub 2} at {theta}{sub F}=0 and 90 deg., in agreement with experiment. Other calculations, including the MO-ADK model and methods involving a numerical integration of the time-dependent Schroedinger equation, exhibit substantially weaker suppression at these angles.

• OSTI ID: 21408451
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 3 Vol. 81; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
APPROXIMATIONS
CALCULATION METHODS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
COMPARATIVE EVALUATIONS
DIFFERENTIAL EQUATIONS
EQUATIONS
EVALUATION
IONIZATION
MOLECULAR ORBITAL METHOD
MOLECULES
OXIDES
OXYGEN COMPOUNDS
PARTIAL DIFFERENTIAL EQUATIONS
PEAKS
SCHROEDINGER EQUATION
SEMICLASSICAL APPROXIMATION
TIME DEPENDENCE
TUNNEL EFFECT
WAVE EQUATIONS