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Trionic and quartetting phases in one-dimensional multicomponent ultracold fermions

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 نشر من قبل Lecheminant
 تاريخ النشر 2008
  مجال البحث فيزياء
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We investigate the possible formation of a molecular condensate, which might be, for instance, the analogue of the alpha condensate of nuclear physics, in the context of multicomponent cold atoms fermionic systems. A simple paradigmatic model of N-component fermions with contact interactions loaded into a one-dimensional optical lattice is studied by means of low-energy and numerical approaches. For attractive interaction, a quasi-long-range molecular superfluid phase, formed from bound-states made of N fermions, emerges at low density. We show that trionic and quartetting phases, respectively for N=3,4, extend in a large domain of the phase diagram and are robust against small symmetry-breaking perturbations.

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