Macroscopic quantum self-trapping of an ultracold Bose-Fermi mixture in a double-well potential

We study the macroscopic quantum self-trapping effect in a mixture of Bose-Einstein condensate (BEC) and quantum degenerate fermions, confined in a double-well potential with a variable separation between the wells. The fermions form a finite-size cloud that affects the static and dynamical properties of the BEC. In particular, our quasi-analytical and numerical analysis based on a mean-field model shows that the main features of macroscopic quantum self-trapping in a pure bosonic system are modified by the influence of fermions. Both the onset of self-trapping and the properties of the self-trapped state depend on the amount of fermions in the system as well as on the type of inter-species interaction. The properties of the quantum degenerate mixture are explored using realistic parameters for a ⁴⁰K-⁸⁷Rb system.