Abstract Kármán vortex street not only exists in nature, but also widely appears in engineering practice, which is of great significance for understanding superfluid. And parity-time (PT) symmetric potential provides a good platform for the study of Kármán vortex street. In this paper, different patterns of vortex shedding formed behind PT symmetric potential in Bose-Einstein condensate (BEC) are
simulated numerically. Kármán vortex street and others are discovered to emerge in the wake of a moving obstacle with appropriate parameters. Compared with BEC without PT symmetric potential, the frequency and amplitude of the drag force are more complex. The parametric regions of the combined modes are scattered around the Kármán vortex street. Numerical simulations indicate that the imaginary part of the PT symmetric potential affects the vortex structure patterns. Finally, we proposed an experimental protocol that may observe Kármán vortex street.
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