The investigation of vortices in superfluids is a fascinating and active line of research that, by now, has a history spanning over half a century. Starting from the first observations of quantized circulation in liquid helium in the 1950s [1], the field has undergone tremendous progress. Nowadays, dilute-gas Bose-Einstein condensates (BECs) provide a powerful tool with which vortex research can be pushed into new regimes, and several hallmark results have been obtained, reaching from interferometric measurements of the quantum mechanical phase of individual vortices to the direct imaging of large vortex lattices containing over 300 vortices in a regular array [2]. Now Tyler Neely and collaborators at the University of Arizona in the US, the Jack Dodd Center for Quantum Technology in New Zealand, and the University of Queensland in Australia [3] are adding another chapter to the story of vortices in superfluids. They have succeeded in creating vortex dipoles, consisting of a vortex paired with an antivortex, in such a controlled way that the dynamics can be studied in detail. An antivortex differs from a vortex only in the orientation of the circular fluid flow.
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