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Title: Sudden perturbation of hydrogen atoms by intense ultrashort laser pulses

Abstract

We study theoretically how hydrogen atoms respond to intense ultrashort laser pulses of duration {tau} shorter than the inverse of the initial-state energy {epsilon}{sub i}{sup -1}. An analytical expression for the evolution operator S is derived up to the first order of the sudden perturbation approximation. This approximation treats the laser-atom interaction beyond the dipole approximation and yields S as a series in the small parameter {epsilon}{sub i}{tau}. It is shown that the effect of realistic laser pulses on atoms begins at the first order of {epsilon}{sub i}{tau}. Transitions between atomic (nlm) states of different m become possible due to the action of the pulse's magnetic field. Transitions between states of same m and arbitrary l become possible if the static Coulomb potential is taken into account during the pulse.

Authors:
;  [1]
  1. Centre for Atomic, Molecular and Surface Physics, Murdoch University, Perth 6150 (Australia)
Publication Date:
OSTI Identifier:
20786327
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 72; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.72.063402; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; APPROXIMATIONS; ATOMS; COULOMB FIELD; DIPOLES; DISTURBANCES; ENERGY LEVELS; ENERGY-LEVEL TRANSITIONS; HYDROGEN; LASER RADIATION; MAGNETIC FIELDS; PHOTON-ATOM COLLISIONS; PULSES

Citation Formats

Lugovskoy, A. V., and Bray, I.. Sudden perturbation of hydrogen atoms by intense ultrashort laser pulses. United States: N. p., 2005. Web. doi:10.1103/PHYSREVA.72.0.
Lugovskoy, A. V., & Bray, I.. Sudden perturbation of hydrogen atoms by intense ultrashort laser pulses. United States. doi:10.1103/PHYSREVA.72.0.
Lugovskoy, A. V., and Bray, I.. Thu . "Sudden perturbation of hydrogen atoms by intense ultrashort laser pulses". United States. doi:10.1103/PHYSREVA.72.0.
@article{osti_20786327,
title = {Sudden perturbation of hydrogen atoms by intense ultrashort laser pulses},
author = {Lugovskoy, A. V. and Bray, I.},
abstractNote = {We study theoretically how hydrogen atoms respond to intense ultrashort laser pulses of duration {tau} shorter than the inverse of the initial-state energy {epsilon}{sub i}{sup -1}. An analytical expression for the evolution operator S is derived up to the first order of the sudden perturbation approximation. This approximation treats the laser-atom interaction beyond the dipole approximation and yields S as a series in the small parameter {epsilon}{sub i}{tau}. It is shown that the effect of realistic laser pulses on atoms begins at the first order of {epsilon}{sub i}{tau}. Transitions between atomic (nlm) states of different m become possible due to the action of the pulse's magnetic field. Transitions between states of same m and arbitrary l become possible if the static Coulomb potential is taken into account during the pulse.},
doi = {10.1103/PHYSREVA.72.0},
journal = {Physical Review. A},
number = 6,
volume = 72,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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