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Relationship between spin squeezing and single-particle coherence in two-component Bose-Einstein condensates with Josephson coupling

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 نشر من قبل Guang-Ri Jin Dr.
 تاريخ النشر 2009
  مجال البحث فيزياء
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We investigate spin squeezing of a two-mode boson system with a Josephson coupling. An exact relation between the squeezing and the single-particle coherence at the maximal-squeezing time is discovered, which provides a more direct way to measure the squeezing by readout the coherence in atomic interference experiments. We prove explicitly that the strongest squeezing is along the $J_z$ axis, indicating the appearance of atom number-squeezed state. Power laws of the strongest squeezing and the optimal coupling with particle number $N$ are obtained based upon a wide range of numerical simulations.

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