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Hydrodynamic Expansion of a Strongly Interacting Fermi-Fermi Mixture

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 نشر من قبل Rudolf Grimm
 تاريخ النشر 2010
  مجال البحث فيزياء
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We report on the expansion of a Fermi-Fermi mixture of Li-6 and K-40 atoms under conditions of strong interactions realized near the center of an interspecies Feshbach resonance. We observe two different phenomena of hydrodynamic behavior. The first one is the well-known inversion of the aspect ratio. The second one is a collective expansion, where both species stick together and despite of their different masses expand jointly. Our work constitutes a first step to explore the intriguing many-body physics of this novel system.



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