Vortices in dipolar Bose–Einstein condensates in synthetic magnetic field

We study the formation of vortices in a dipolar Bose-Einstein condensate in a synthetic magnetic field by numerically solving the Gross-Pitaevskii equation. The formation process depends on the dipole strength, the rotating frequency, the potential geometry, and the orientation of the dipoles. We make an extensive comparison with vortices created by a rotating trap, especially focusing on the issues of the critical rotating frequency and the vortex number as a function of the rotating frequency. We observe that a higher rotating frequency is needed to generate a large number of vortices and the anisotropic interaction manifests itself as a perceptible difference in the vortex formation. Furthermore, a large dipole strength or aspect ratio also can increase the number of vortices effectively. In particular, we discuss the validity of the Feynman rule.

Cyclotron dynamics of a Bose—Einstein condensate in a quadruple-well potential with synthetic gauge fields

We investigate the cyclotron dynamics of Bose-Einstein condensate(BEC)in a quadruple-well potential with synthetic gauge fields.We use laser-assisted tunneling to generate large tunable effective magnetic fields for BEC.The mean position of BEC follows an orbit that simulated the cyclotron orbits of charged particles in a magnetic field.In the absence of atomic interaction,atom dynamics may exhibit periodic or quasi-periodic cyclotron orbits.In the presence of atomic interaction,the system may exhibit self-trapping,which depends on synthetic gauge fields and atomic interaction strength.In particular,the competition between synthetic gauge fields and atomic interaction leads to the generation of several discontinuous parameter windows for the transition to self-trapping,which is obviously different from that without synthetic gauge fields.

Trapped Bose-Einstein condensates in synthetic magnetic field

The rotational properties of Bose-Einstein condensates in a synthetic magnetic field are studied by numerically solving the Gross-Pitaevskii equation and comparing the results to those of condensates confined in a rotating trap. It appears to be more difficult to add a large angular momentum to condensates spun up by the synthetic magnetic field than by the rotating trap. However, strength- ening the repulsive interaction between atoms is an effective and realizable route to overcoming this problem and can at least generate vortex-lattice-like structures. In addition, the validity of the Feynman rule for condensates in the synthetic magnetic field is verified.