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Ionization of Xe in intense, two-cycle laser fields: Dependence on carrier-envelope phase

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 نشر من قبل Deepak Mathur
 تاريخ النشر 2017
  مجال البحث فيزياء
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We report on tunnel ionization of Xe by 2-cycle, intense, infrared laser pulses and its dependence on carrier-envelope-phase (CEP). At low values of optical field ($E$), the ionization yield is maximum for cos-like pulses with the dependence becoming stronger for higher charge states. At higher $E$-values, the CEP dependence either washes out or flips. A simple phenomenological model is developed that predicts and confirms the observed results. CEP effects are seen to persist for 8-cycle pulses. Unexpectedly, electron rescattering plays an unimportant role in the observed CEP dependence. Our results provide fresh perspectives in ultrafast, strong-field ionization dynamics of multi-electron systems that lie at the core of attosecond science.



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