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Universal behavior of pair correlations in a strongly interacting Fermi gas

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 نشر من قبل Chris Vale
 تاريخ النشر 2010
  مجال البحث فيزياء
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We show that short-range pair correlations in a strongly interacting Fermi gas follow a simple universal law described by Tans relations. This is achieved through measurements of the static structure factor which displays a universal scaling proportional to the ratio of Tans contact to the momentum $C/q$. Bragg spectroscopy of ultracold $^6$Li atoms from a periodic optical potential is used to measure the structure factor for a wide range of momenta and interaction strengths, providing broad confirmation of this universal law. We calibrate our Bragg spectra using the $f$-sum rule, which is found to improve the accuracy of the structure factor measurement.



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