Trimers, molecules, and polarons in mass-imbalanced atomic Fermi gases.

  title={Trimers, molecules, and polarons in mass-imbalanced atomic Fermi gases.},
  author={Charles Mathy and Meera M. Parish and David A. Huse},
  journal={Physical review letters},
  volume={106 16},
We consider the ground state of a single "spin-down" impurity atom interacting attractively with a "spin-up" atomic Fermi gas. By constructing variational wave functions for polarons, molecules, and trimers, we perform a detailed study of the transitions between these dressed bound states as a function of mass ratio r=m↑/m↓ and interaction strength. Crucially, we find that the presence of a Fermi sea enhances the stability of the p-wave trimer, which can be viewed as a Fulde-Ferrell-Larkin… 

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