Vortex dynamics in binary ultracold Rydberg atomic system

The vortex dynamics after the initial ring dark solitons in two-component ultracold Rydberg atomic systems have been investigated. The two parameters characterizing the Rydberg long-range interaction|namely, the Rydberg strength and the blockade radius|along with the initial depth, are identified as the main factors that affect the vortex dynamics. In the absence of Rydberg soft-core potential and spin-orbit coupling, the late vortex dipoles move along x- or y-axis first. While this work demonstrates that the Rydberg nonlocal nonlinear interaction shorten the lifetime of late vortices, it also shows that, with certain Rydberg strength and blockade radius, the late vortex dipoles move towards the edge at an oblique angle to the coordinate axes. When the intra-component and inter-component Rydberg strengths are different, the backgrounds of the two components gradually complement each other, and the lifetime of late vortices is significantly shortened. The presented results show that the Rydberg dressing breaks the rule that the initial average depth determines the number and paths of vortices. The motion features of vortex dipoles in ultracold Rydberg atomic system have been ascertained, and their directions of movement can be predicted to some degree based on the rotation directions and initial positions of the vortices.