Mateo, DavidLeal, AntonioHernando, AlbertoBarranco, ManuelPi, MartiCargnoni, FaustoMella, MassimoZhang, XiaohangDrabbels, Marcel2013-12-202013-12-202013-12-20201410.1063/1.4870245https://infoscience.epfl.ch/handle/20.500.14299/98611WOS:000334577300001Whereas most of the phenomena associated with superfluidity have been observed in finite-size helium systems, the nucleation of quantized vortices has proven elusive. Here we show that the solvation of a Ba+ ion created by photoionization of neutral Ba at the surface of a 4He nanodroplet leads to the nucleation of a quantized ring vortex. The vortex is nucleated on a ten picosecond timescale at the equator of a solid-like solvation structure that forms around the Ba+ ion. The process is expected to be quite general and very efficient under standard experimental conditions.Photoionizationsuperfluidsolvationtext::journal::journal article::research article