Using laser beams, scientists generate quantum matter with novel, crystal-like properties

Using laser beams, scientists generate quantum matter with novel, crystal-like properties:  As the scientists chose Rydberg-states which give rise to repulsive van der Waals forces the excited atoms have to keep a minimum distance of several micrometers from each other. This mutual blockade leads to spatial correlations between the atoms such that, depending on the number of Rydberg-atoms, states with different geometrical configurations can emerge (see fig. 1). "However, we have to be aware that in our excited quantum system all geometrical orders are present at the same time. To be precise, all the excitation states form a coherent superposition, " Dr. Marc Cheneau says, a scientist at the experiment. "This new state of matter is a very fragile, crystal-like formation; it exists as long as the excitation is sustained, and fades away once the beam is switched off."