Correlated Tunneling Dynamics of an Ultracold Fermi-Fermi Mixture Confined in a Double-Well

TL;DR

This paper investigates the complex tunneling behavior of a mass-imbalanced ultracold fermionic mixture in a double-well, revealing how interactions and system parameters influence dynamics, entanglement, and experimental observables.

Contribution

It provides a detailed analysis of correlated tunneling dynamics, entanglement, and experimental signatures in a mass-imbalanced Fermi-Fermi mixture under various interaction regimes.

Findings

Transition from Rabi-oscillations to delayed tunneling with increasing interactions

Quantum self-trapping of lighter species due to heavier species acting as a barrier

Significant entanglement observed at moderate and strong interactions

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 non-equilibrium dynamics of both species changes from Rabi-oscillations close to the non-interacting 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 both at moderate and strong repulsions. To relate our findings with 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.