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Retrieval of electron-atom scattering cross sections from laser-induced electron rescattering of atomic negative ions in intense laser fields

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 نشر من قبل Zhangjin Chen
 تاريخ النشر 2007
  مجال البحث فيزياء
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We investigated the two-dimensional electron momentum distributions of atomic negative ions in an intense laser field by solving the time-dependent Schrodinger equation (TDSE) and using the first- and 2nd-order strong-field approximations (SFA). We showed that photoelectron energy distributions and low-energy photoelectron momentum spectra predicted from SFA are in reasonable agreement with the solutions from the TDSE. More importantly, we showed that accurate electron-atom elastic scattering cross sections can be retrieved directly from high-energy electron momentum spectra of atomic negative ions in the laser field. This opens up the possibility of measuring electron-atom and electron-molecule scattering cross sections from the photodetachment of atomic and molecular negative ions by intense short lasers, respectively, with temporal resolutions in the order of femtoseconds.



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