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Expansion of matter waves in static and driven periodic potentials

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 نشر من قبل Charles Creffield
 تاريخ النشر 2010
  مجال البحث فيزياء
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We study the non-equilibrium dynamics of cold atoms held in an optical lattice potential. The expansion of an initially confined atom cloud occurs in two phases: an initial quadratic expansion followed by a ballistic behaviour at long times. Accounting for this gives a good description of recent experimental results, and provides a robust method to extract the effective intersite tunneling from time-of-flight measurements.



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