arXiv:1809.00908 · Physical Review A

Correlated tunneling dynamics of an ultracold Fermi-Fermi mixture confined in a double well

J. Erdmann, S. I. Mistakidis, Peter Schmelcher

Published Nov 12, 2018• 32 citations

Abstract

We unravel the correlated tunneling dynamics of a mass imbalanced few-body Fermi-Fermi mixture upon quenching the tilt of a double well. The nonequilibrium dynamics of both species changes from Rabi oscillations close to the noninteracting limit to a delayed tunneling dynamics for moderate interspecies repulsions. Considering strong interspecies interactions, the lighter species experiences quantum self-trapping due to the heavier species which acts as an effective material barrier, while performing almost perfect Rabi oscillations. The degree of entanglement, inherent in the system, is analyzed and found to be significant at both moderate and strong repulsions. To relate our findings to possible experimental realizations, we simulate in situ single-shot measurements and discuss how a sampling of such images dictates the observed dynamics. Finally, the dependence of the tunneling behavior on the mass ratio, the particle number in each species, and the height of the barrier of the double well is showcased.

DOI: 10.1103/physreva.98.053614

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