Phase transitions describe dramatic changes in properties of a macroscopic system - like the transition from a liquid to a gas. Starting from individual ultracold atoms, physicists were able to observe the emergence of such a transition with an increasing number of particles.
The MRI system made by the researchers makes use of a special lattice defect in the crystal structure of diamonds. This defect - known as nitrogen-vacancy centre - enables high-resolution imaging of the magnetic structure of a sample.
