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Probing quantum statistical mechanics with Bose gases: Non-trivial order parameter topology from a Bose-Einstein quench

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 نشر من قبل James R. Anglin
 تاريخ النشر 2000
  مجال البحث فيزياء
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This is a less technical presentation of the ideas in quant-ph/9804035 [Phys Rev Lett 83 (1999), 1707-1710]. A second order phase transition induced by a rapid quench can lock out topological defects with densities far exceeding their equilibrium expectation values. This phenomenon is a generic prediction of nonequilibrium statistical mechanics, and can appear in a wide range of physical systems. We discuss it qualitatively in the context of trapped dilute Bose-Einstein condensates, outline a simple quantitative theory based on the time-dependent Ginzburg-Landau equation, and briefly compare the results of quantum kinetic theory.



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