Researchers predict that strongly interacting bosons and fermions can form stable quantum droplets that may be testable with current experiments.

Two very different kinds of quantum particles may be able to join together in a stable form of matter that physicists once considered unlikely. Researchers at Monash University predict that ultracold bosons and fermions can combine under the right conditions to create self-bound “quantum droplets.”

Bosons and fermions follow fundamentally different quantum rules, yet the new theoretical work indicates that strongly interacting mixtures of the two can remain bound together. The result challenges the long-held expectation that stable droplets would be difficult to form in strongly interacting Bose-Fermi systems.