- Titel
- Revealing quantum effects in bosonic Josephson junctions
- Untertitel
- a multi-configuration atomic coherent state approach
- Zitierfähige Url:
- https://nbn-resolving.org/urn:nbn:de:bsz:14-qucosa2-948699
- Quellenangabe
- Frontiers in physics
Erscheinungsjahr: 2023
Jahrgang: 11
E-ISSN: 2296-424X
Artikelnummer: 1221614 - Erstveröffentlichung
- 2023
- Abstract (EN)
- The mean-field approach to two-site Bose–Hubbard systems is well-established and leads to non-linear classical equations of motion for population imbalance and phase difference. It can, for example, be based on the representation of the solution of the time-dependent Schrödinger equation either by a single Glauber state or by a single atomic (SU(2)) coherent state [S. Wimberger et al., Phys. Rev. A 103, 023326 (2021)]. We demonstrate that quantum effects beyond the mean-field approximation are easily uncovered if, instead, a multiconfiguration ansatz with a few time-dependent SU(2) basis functions is used in the variational principle. For the case of plasma oscillations, the use of just two basis states, whose time-dependent parameters are determined variationally, already gives a good qualitative agreement of the phase space dynamics with numerically exact quantum solutions. In order to correctly account for more non-trivial effects, like macroscopic quantum self-trapping, moderately more basis states are needed. For the onset of spontaneous symmetry breaking, however, a multiplicity of 2 gives a significant improvement already. In any case, the number of variational trajectories needed for good agreement with the full quantum results is orders of magnitude smaller than that in the semi-classical case, which is based on multiple mean-field trajectories.
- Andere Ausgabe
- Link zum Artikel, der zuerst in der Zeitschrift „Frontiers in physics” im Verlag Frontiers Media erschienen ist.
DOI: 10.3389/fphy.2023.1221614 - Freie Schlagwörter (EN)
- bosonic Josephson junction, atomic coherent state, variational principle, timedependent Schrödinger equation, multiconfiguration ansatz
- Klassifikation (DDC)
- 530
- Verlag
- Frontiers Media, Lausanne
- Version / Begutachtungsstatus
- publizierte Version / Verlagsversion
- URN Qucosa
- urn:nbn:de:bsz:14-qucosa2-948699
- Veröffentlichungsdatum Qucosa
- 05.11.2025
- Dokumenttyp
- Artikel
- Sprache des Dokumentes
- Englisch
- Lizenz / Rechtehinweis
CC BY 4.0