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Critical velocity in resonantly driven polariton superfluids

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 نشر من قبل Amandine Aftalion
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف Simon Pigeon




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We study the necessary condition under which a resonantly driven exciton polariton superfluid flowing against an obstacle can generate turbulence. The value of the critical velocity is well estimated by the transition from elliptic to hyperbolic of an operator following ideas developed by Frisch, Pomeau, Rica for a superfluid flow around an obstacle, though the nature of equations governing the polariton superfluid is quite different. We find analytical estimates depending on the pump amplitude and on the pump energy detuning, quite consistent with our numerical computations.



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