The effects of trapconfinement and interatomic interactions on Josephson effects and macroscopic quantum selftrapping for a BoseEinstein condensate
Abstract
We theoretically study the effects of trapconfinement and interatomic interactions on Josephson oscillations (JO) and macroscopic quantum selftrapping (MQST) for a BoseEinstein condensate confined in a trap which has a symmetric doublewell potential along zaxis and 2D harmonic potentials along x and yaxis. We consider three types of model interaction potentials: contact, longrange dipolar and finiterange potentials. Our results show that by changing the aspect ratio between the axial and radial trap sizes, one can induce a transition from JO to MQST for contact interactions with a small scattering length. For longrange dipolar interatomic interactions, we analyze transition from Rabi to Josephson regime and Josephson to MQST regime by changing the aspect ratio of the trap for a particular dipolar orientation. For a finiterange interaction, we study the effects of relatively large scattering length and effective range on JO and MQST. We show that JO and MQST are possible even if scattering length is relatively large, particularly near a narrow Feshbach resonance due to the finiterange effects.
 Publication:

Journal of Physics B Atomic Molecular Physics
 Pub Date:
 August 2019
 DOI:
 10.1088/13616455/ab2b58
 arXiv:
 arXiv:1903.07417
 Bibcode:
 2019JPhB...52o5301S
 Keywords:

 Josephson oscillations;
 macroscopic quantum selftrapping;
 trapconfinement;
 interatomic interactions;
 Bose–Einstein condensate;
 double well;
 Physics  Atomic Physics;
 Condensed Matter  Quantum Gases
 EPrint:
 doi:10.1088/13616455/ab2b58