Quench-induced resonant tunneling mechanisms of bosons in an optical lattice with harmonic confinement

TL;DR

This paper investigates how sudden changes in harmonic confinement influence the non-equilibrium dynamics of small boson ensembles in a 1D optical lattice, revealing resonant tunneling mechanisms linked to avoided crossings in the spectrum.

Contribution

It uncovers the role of avoided crossings in resonant tunneling and demonstrates how to utilize these for state preparation in bosonic systems.

Findings

Resonant response occurs at intermediate quench amplitudes.

Avoided crossings in the eigenspectrum enable controlled state preparation.

The dynamical response depends on interaction strength and atom number.

Abstract

The non-equilibrium dynamics of small boson ensembles in a one-dimensional optical lattice is explored upon a sudden quench of an additional harmonic trap from strong to weak confinement. We find that the competition between the initial localization and the repulsive interaction leads to a resonant response of the system for intermediate quench amplitudes, corresponding to avoided crossings in the many-body eigenspectrum with varying final trap frequency. In particular, we show that these avoided crossings can be utilized to prepare the system in a desired state. The dynamical response is shown to depend on both the interaction strength as well as the number of atoms manifesting the many-body nature of the tunneling dynamics.