Physicists from Monash University and Heidelberg University have described a possible new form of quantum matter: a stable droplet made from bosons and fermions, two different classes of quantum particles.
Writing in Physical Review Letters, the researchers used a theoretical model to study what happens when the particles interact strongly. Their calculations suggest that an attraction between the particles can be balanced by pressure from the fermions, keeping the droplet from collapsing.
The paper says the effect could occur in experimentally available mixtures of ultracold atoms when the particle masses are close to one another. That gives other scientists a possible way to test the prediction in a laboratory.
The work also points to phase changes that resemble a liquid turning into a gas. It is basic research for now, but it gives scientists another place to look for the rules that shape unusual quantum systems.
