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Macroscopic Rabi-Like Oscillations of Ultracold Atoms in an Asymmetrical Two-Dimensional Magnetic Lattice

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 نشر من قبل Ahmed Abdelrahman
 تاريخ النشر 2010
  مجال البحث فيزياء
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We investigate the existence of the $macroscopic$ $quantum$ $phase$ in trapped ultracold quantum degenerate gases, such as Bose-Einstein condensate, in an asymmetrical two-dimensional magnetic lattice. We show the key to adiabatically control the tunneling in the new two-dimensional magnetic lattice by means of external magnetic bias fields. The macroscopic quantum phase signature is identified as a Rabi-like oscillation when solving the system of coupled time-dependent differential equations, described here by the Boson Josephson Junctions (BJJs). In solving the system of the BJJs we used an order parameter that includes both time-dependent variational parameters which are the fractional population at each lattice site and the phase difference. The BJJs solution presents a clear evidence for the macroscopic quantum coherence.



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