2019/06/30 by S. K. Adhikari · 1 citation
Physics and Astronomy · #cond-mat.quant-gas #nlin.PS
paper · pdf · doi:10.1088/1612-202x/ab2d2c
published as Laser Phys. Lett. 16 (2019) 085501
arxiv created 2019/07/04 · arxiv updated 2019/08/20
In a harmonically-trapped rotating Bose-Einstein condensate (BEC), a vortex of large angular momentum decays to multiple vortices of unit angular momentum from an energetic consideration. We demonstrate the formation of a robust and dynamically stable giant vortex of large angular momentum in a harmonically trapped rotating BEC with a potential hill at the center, thus forming a Mexican hat like trapping potential. For a small inter-atomic interaction strength, a highly controllable stable giant vortex appears, whose angular momentum slowly increases as the angular frequency of rotation is increased. As the inter-atomic interaction strength is increased beyond a critical value, only vortices of unit angular momentum are formed, unless the strength of the potential hill at the center is also increased: for a stronger potential hill at the center a giant vortex is again formed. The dynamical stability of the giant vortex is demonstrated by real-time propagation numerically. These giant vortices of large angular momentum can be observed and studied experimentally in a highly controlled fashion.