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Hyperpolarizability effects in a Sr optical lattice clock

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 نشر من قبل Pierre Lemonde
 تاريخ النشر 2005
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Anders Brusch




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We report the observation of the higher order frequency shift due to the trapping field in a $^{87}$Sr optical lattice clock. We show that at the magic wavelength of the lattice, where the first order term cancels, the higher order shift will not constitute a limitation to the fractional accuracy of the clock at a level of $10^{-18}$. This result is achieved by operating the clock at very high trapping intensity up to $400 $kW/cm$^2$ and by a specific study of the effect of the two two-photon transitions near the magic wavelength.



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