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Title: Two-dimensional electron momentum spectra of argon ionized by short intense lasers: Comparison of theory with experiment

Abstract

We studied the two-dimensional electron momentum spectra of Ar by femtosecond intense laser pulses with mean wavelength from 400 nm to 800 nm, to compare with experimental results of Maharjan et al. [J. Phys. B 39, 1955 (2006)]. At the higher intensities we found that the effects of ground-state depletion and laser-focus volume are very important such that the peak laser field strength is not reached in experiment. The ubiquitous fanlike stripes in the low-energy electron momentum spectra and the evidence of Freeman resonances in the experimental data are well reproduced in the theoretical calculations. We emphasize that depletion of the initial state should be carefully evaluated for ionization of atoms in the tunneling region.

Authors:
 [1];  [2]; ;  [3];  [1]
  1. Department of Applied Physics and Chemistry, University of Electro-Communications, 1-5-1 Chofu-ga-oka, Chofu-shi, Tokyo 182-8585 (Japan)
  2. (United States)
  3. Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States)
Publication Date:
OSTI Identifier:
20982145
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.023407; (c) 2007 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; ARGON; ATOMS; COMPARATIVE EVALUATIONS; ELECTRON SPECTRA; ELECTRONS; GROUND STATES; LASER RADIATION; PHOTOIONIZATION; PHOTON-ATOM COLLISIONS; PULSES; RESONANCE; TUNNEL EFFECT; TUNNELING; TWO-DIMENSIONAL CALCULATIONS; WAVELENGTHS

Citation Formats

Morishita, Toru, Department of Physics, Kansas State University, Manhattan, Kansas 66506, Chen, Zhangjin, Lin, C. D., and Watanabe, Shinichi. Two-dimensional electron momentum spectra of argon ionized by short intense lasers: Comparison of theory with experiment. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.023407.
Morishita, Toru, Department of Physics, Kansas State University, Manhattan, Kansas 66506, Chen, Zhangjin, Lin, C. D., & Watanabe, Shinichi. Two-dimensional electron momentum spectra of argon ionized by short intense lasers: Comparison of theory with experiment. United States. doi:10.1103/PHYSREVA.75.023407.
Morishita, Toru, Department of Physics, Kansas State University, Manhattan, Kansas 66506, Chen, Zhangjin, Lin, C. D., and Watanabe, Shinichi. Thu . "Two-dimensional electron momentum spectra of argon ionized by short intense lasers: Comparison of theory with experiment". United States. doi:10.1103/PHYSREVA.75.023407.
@article{osti_20982145,
title = {Two-dimensional electron momentum spectra of argon ionized by short intense lasers: Comparison of theory with experiment},
author = {Morishita, Toru and Department of Physics, Kansas State University, Manhattan, Kansas 66506 and Chen, Zhangjin and Lin, C. D. and Watanabe, Shinichi},
abstractNote = {We studied the two-dimensional electron momentum spectra of Ar by femtosecond intense laser pulses with mean wavelength from 400 nm to 800 nm, to compare with experimental results of Maharjan et al. [J. Phys. B 39, 1955 (2006)]. At the higher intensities we found that the effects of ground-state depletion and laser-focus volume are very important such that the peak laser field strength is not reached in experiment. The ubiquitous fanlike stripes in the low-energy electron momentum spectra and the evidence of Freeman resonances in the experimental data are well reproduced in the theoretical calculations. We emphasize that depletion of the initial state should be carefully evaluated for ionization of atoms in the tunneling region.},
doi = {10.1103/PHYSREVA.75.023407},
journal = {Physical Review. A},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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