Petar Jurcevic et al., PRL 119, 080501
Today, the equilibrium properties of quantum matter are theoretically described with great success. Yet, in recent years pioneering experiments have created quantum states beyond this equilibrium paradigm. Understanding properties of such nonequilibrium quantum states on a general level provides a significant challenge. Jurcevic at el. have now experimentally observed for the first time a phenomenon - a dynamical quantum phase transition - which promises to provide a general framework to identify and predict such general principles of quantum dynamics.
See also the Physics Viewpoint: Quantum Phase Transitions Go Dynamical