Physical Review A
Structure and generation of the vortex-antivortex superposed state in Bose-Einstein condensates
M. Liu, Linghua Wen, Hongwei Xiong, Mingsheng Zhan
Abstract
We investigate the properties of the vortex-antivortex superposed state for a Bose-Einstein condensate confined in a harmonic potential. The density distribution of the vortex-antivortex superposed state has a petal structure which is determined by the quantum circulations and proportion of the vortex and antivortex. Based on the Gross-Pitaevskii equation, we show that this vortex-antivortex superposed state can be stable through both analytical derivation and numerical calculations. Furthermore, we propose a feasible scheme to generate a coherently superposed vortex-antivortex state with arbitrary proportion by compressing and rehabilitating the harmonic trap with specific time order, which is proven by numerical simulations.