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Spontaneous generation of quantum turbulence through the decay of a giant vortex in a two-dimensional superfluid

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 تاريخ النشر 2014
  مجال البحث فيزياء
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We show the generation of two-dimensional quantum turbulence through simulations of a giant vortex decay in a trapped Bose-Einstein condensate. While evaluating the incompressible kinetic energy spectra of the quantum fluid described by the Gross-Pitaevskii equation, a bilinear form in a log-log plot is verified. A characteristic scaling behavior for small momenta shows resemblance to the Kolmogorov $k^{-5/3}$ law, while for large momenta it reassures the universal behavior of the core-size $k^{-3}$ power-law. This indicates a mechanism of energy transportation consistent with an inverse cascade. The feasibility of the described physical system with the currently available experimental techniques to create giant vortices opens up a new route to explore quantum turbulence.



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