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Dynamics of Macroscopic Tunneling in Elongated BEC

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 نشر من قبل Fleurov Victor
 تاريخ النشر 2009
  مجال البحث فيزياء
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We investigate macroscopic tunneling from an elongated quasi 1-d trap, forming a cigar shaped BEC. Using recently developed formalism we get the leading analytical approximation for the right hand side of the potential wall, i.e. outside the trap, and a formalism based on Wigner functions, for the left side of the potential wall, i.e. inside the BEC. We then present accomplished results of numerical calculations, which show a blip in the particle density traveling with an asymptotic shock velocity, as resulted from previous works on a dot-like trap, but with significant differences from the latter. Inside the BEC a pattern of a traveling dispersive shock wave is revealed. In the attractive case, we find trains of bright solitons frozen near the boundary.



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