Unconventional pairing in few-fermion systems tuned by external confinement

  title={Unconventional pairing in few-fermion systems tuned by external confinement},
  author={Jacek Dobrzyniecki and Giuliano Orso and Tomasz Sowi'nski},
  journal={Physical Review Research},
We study the ground-state properties of a two-component one-dimensional system of a few ultracold fermions with attractive interactions. We show that, by ramping up an external potential barrier felt by one of the components, it is possible to induce regions of exotic superfluid phases, characterized by a tunable finite net momentum of the Cooper pair, without changing the overall spin populations. We show that these phases, which are the few-body analogs of the celebrated Fulde-Ferrell-Larkin… 

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