Supersolid state synchronizes under rotation unlocking quantum vortex behavior

A supersolid is an unusual state of matter showing both crystal rigidity and frictionless flow, a paradox realized only in recent years within dipolar quantum gases. Researchers at the University of Innsbruck, led by Francesca Ferlaino, investigated how the solid and superfluid features of a supersolid behave when rotated. Using precisely controlled magnetic fields, the team induced rotation in a supersolid quantum gas and observed a distinct phenomenon: "The quantum droplets of the supersolid are in a crystal-like periodic order, all dressed by a superfluid between them," explains Francesca Ferlaino. "Each droplet precesses following the rotation of the external magnetic field; they all revolve collectively. When a vortex enters the system, precession and revolution begins to rotate synchronously."

Elena Poli, who developed the theoretical model, reported, "What surprised us was that the supersolid crystal didn't just rotate chaotically. Once quantum vortices formed, the whole structure fell into rhythm with the external magnetic field-like nature finding its own beat."

Andrea Litvinov, who handled the experiments, commented, "It was thrilling to see the data suddenly align with the theory. There was a moment when the system just 'snapped into rhythm'."

The team explained that synchronization of components-a common natural behavior among pendulum clocks, fireflies, or heart cells-was now demonstrated in exotic quantum matter. This allowed for precise measurement of the critical frequency where vortices emerge, a property in rotating quantum fluids that previously proved hard to determine directly.

Advanced simulations worked hand-in-hand with intricate experiments using ultracold atoms of dysprosium, cooled near absolute zero. The researchers applied a technique called magnetostirring to rotate the supersolid and tracked its evolution with high accuracy.

Their findings, published in Nature Physics, promise relevance beyond laboratory confines: similar vortex dynamics may influence "glitches" in neutron stars, among the universe's densest objects. "Supersolids are a perfect playground to explore questions that are otherwise inaccessible," stated Poli. "While these systems are created in micrometer-sized laboratory traps, their behavior may echo phenomena on cosmic scales."

"This work was made possible by the close collaboration between theory and experiment-and the creativity of the young researchers on our team," said Ferlaino of the University of Innsbruck's Department of Experimental Physics and the Institute for Quantum Optics and Quantum Information (IQOQI) at the Austrian Academy of Sciences. The research was a partnership with the University of Trento's Pitaevskii BEC Center and was supported by the Austrian Science Fund (FWF), the Austrian Research Promotion Agency (FFG), and the European Union.

Research Report:Synchronization in rotating supersolids