Differences between mean-field dynamics and N-particle quantum dynamics as a signature of entanglement

TL;DR

This paper investigates how differences between mean-field and N-particle quantum dynamics in a Bose-Einstein condensate can reveal the presence of entanglement, especially in chaotic regimes, highlighting the role of mesoscopic entangled states.

Contribution

It demonstrates that discrepancies between mean-field and quantum dynamics serve as signatures of entanglement in chaotic regimes of a BEC in a double-well potential.

Findings

Differences persist even after averaging over oscillations.

Decoherence reduces but does not eliminate these differences.

Chaotic regimes produce mesoscopic entangled states.

Abstract

A Bose-Einstein condensate in a tilted double-well potential under the influence of time-periodic potential differences is investigated in the regime where the mean-field (Gross-Pitaevskii) dynamics become chaotic. For some parameters near stable regions, even averaging over several condensate oscillations does not remove the differences between mean-field and N-particle results. While introducing decoherence via piecewise deterministic processes reduces those differences, they are due to the emergence of mesoscopic entangled states in the chaotic regime.