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Generalized gauge-invariant formulations of the strong-field approximation

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 نشر من قبل Yulian Vanne
 تاريخ النشر 2008
  مجال البحث فيزياء
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The gauge problem in the so-called strong-field approximation (SFA) describing atomic or molecular systems exposed to intense laser fields is investigated. Introducing a generalized gauge and partitioning of the Hamiltonian it is demonstrated that the S-matrix expansion obtained in the SFA depends on both gauge and partitioning in such a way that two gauges always yield the same S-matrix expansion, if the partitioning is properly chosen.



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