An international study published in Nature Communications, coordinated by the National Optics Institute of the National Research Council (CNR INO) in Florence, studied the dynamics of vortices in highly interacting superfluids, identifying their fundamental mechanisms.

The study was carried out by the research group of Giacomo Roati at CNR INO, Francesco Scazza, associate professor of Physics of the Matter at UniTS, and the universities of Florence, Bologna, Warsaw University of Technology and the University of Augusta (Germany). 

 The investigated ‘vortexes’ are small reels of fluid that revolve around an axis, inside a lithium atom gas cooled to extremely low temperatures, just 10 billionths of a degree above absolute zero. Under these conditions, matter enters a state called superfluid, in which the viscosity disappears and the fluid flows without friction. The superfluid behavior of ultracold atoms is analogous to that of superconductors, where electric current can circulate without resistance, allowing the transport of current without loss of energy. In both systems, vortex dynamics play a key role as they can open a channel for energy dissipation.

Giacomo Roati, CNR-INO Research Manager at LENS and Head of the Research Group, explains: ‘The use of ultra-cold atomic gases has allowed us to study this phenomenon in a very controlled way, within real “quantum simulations”. The dynamics of the vortexes in the case studied share similarities with that in high-temperature superconductors, a field still under study. Understanding their motion is essential to assess dissipative effects and to design new high-efficiency superconducting systems, in which these effects can be minimised in a targeted manner, paving the way for cutting-edge quantum technologies.’