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Title: Time delay in strong-field photoionization of a hydrogen atom

Abstract

We study time delay for the process of photoionization of a hydrogen atom in a strong electromagnetic field. We compute this quantity by solving the time-dependent Schroedinger equation. We show that even a moderately strong field can have quite a considerable effect on the time delay. Analysis of the wave-packet motion performed by means of the Gabor transform shows that a simple semiclassical model can explain this phenomenon.

Authors:
 [1]
  1. Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200 (Australia)
Publication Date:
OSTI Identifier:
21537187
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 83; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.83.023421; (c) 2011 American Institute of Physics
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; ELECTROMAGNETIC FIELDS; HYDROGEN; PHOTOIONIZATION; SCHROEDINGER EQUATION; SEMICLASSICAL APPROXIMATION; TIME DELAY; TIME DEPENDENCE; WAVE PACKETS; APPROXIMATIONS; CALCULATION METHODS; DIFFERENTIAL EQUATIONS; ELEMENTS; EQUATIONS; IONIZATION; NONMETALS; PARTIAL DIFFERENTIAL EQUATIONS; WAVE EQUATIONS

Citation Formats

Ivanov, I. A. Time delay in strong-field photoionization of a hydrogen atom. United States: N. p., 2011. Web. doi:10.1103/PHYSREVA.83.023421.
Ivanov, I. A. Time delay in strong-field photoionization of a hydrogen atom. United States. doi:10.1103/PHYSREVA.83.023421.
Ivanov, I. A. Tue . "Time delay in strong-field photoionization of a hydrogen atom". United States. doi:10.1103/PHYSREVA.83.023421.
@article{osti_21537187,
title = {Time delay in strong-field photoionization of a hydrogen atom},
author = {Ivanov, I. A.},
abstractNote = {We study time delay for the process of photoionization of a hydrogen atom in a strong electromagnetic field. We compute this quantity by solving the time-dependent Schroedinger equation. We show that even a moderately strong field can have quite a considerable effect on the time delay. Analysis of the wave-packet motion performed by means of the Gabor transform shows that a simple semiclassical model can explain this phenomenon.},
doi = {10.1103/PHYSREVA.83.023421},
journal = {Physical Review. A},
number = 2,
volume = 83,
place = {United States},
year = {Tue Feb 15 00:00:00 EST 2011},
month = {Tue Feb 15 00:00:00 EST 2011}
}
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  • We describe atomic hydrogen diamagnetism within the framework of multichannel quantum-defect theory using an {ital R}-matrix approach. The calculated photoionization spectrum in the range of magnetic field {ital B}=10{sup 3}--10{sup 4} T shows that the quasi-Landau resonances are broad interlopers that perturb high Rydberg states converging to the Landau thresholds, forming complex resonances. A partial-cross-section analysis indicates that electron population of different Landau channels depends on the azimuthal quantum number and parity of the final states. For odd-total-parity final states with {ital m}=1, the photoionized electron is predicted to escape predominantly in the higher Landau channels, while for final statesmore » with {ital m}=0, it escapes in the lower channels. This property is reflected in the shape of autoionizing resonances, which are more like peaks for {ital m}=1, but are more like dips (window resonances) for {ital m}=0.« less
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