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Enhancing keV high harmonic signals generated by long-wave infrared lasers

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 نشر من قبل Zenghu Chang
 تاريخ النشر 2019
  مجال البحث فيزياء
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 تأليف Zenghu Chang




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It is demonstrated by single-atom simulations that X-ray signals in the 3.4 to 4 keV region from an 8 micron laser driven high harmonic generation can be increased by more than two orders of magnitude when a single-cycle pulse centered at 800 nm is added. The ionization probability of a helium atom by the two-pulse field is set to 4.56x10^-5, which is needed for balancing the index of refraction of free electrons with that of neutral helium atoms to achieve phase matching.



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