Chaos and bi-partite entanglement between Bose-Joephson junctions
Abstract
The entanglement between two weakly coupled bosonic Josephson junctions is studied in relation to the classical mixed phasespace structure of the system, containing symmetry-related regular islands separated by chaos. The symmetry-resolved entanglement spectrum and bi-partite entanglement entropy of the system's energy eigenstates are calculated and compared to their expected structure for random states that exhibit complete or partial ergodicity. The entanglement spectra of chaos-supported eigenstates match the microcanonical structure of a Generalized Gibbs Ensemble due to the existence of an adiabatic invariant that restricts ergodization on the energy shell. The symmetry-resolved entanglement entropy of these quasistochastic states consists of a mean-field maximum entanglement term and a fluctuation correction due to the finite size of the constituent subsystems. The total bi-partite entanglement entropy of the eigenstates correlates with their chaoticity. Island-supported eigenstates are macroscopic Schr\"odinger cat states for particles and excitations, with substantially lower entanglement.
Keywords
Cite
@article{arxiv.2208.08192,
title = {Chaos and bi-partite entanglement between Bose-Joephson junctions},
author = {Amichay Vardi},
journal= {arXiv preprint arXiv:2208.08192},
year = {2023}
}
Comments
9 pages, 8 figures