Credit: Image courtesy of Nathan Gemelke and Cheng Chin, University of Chicago
These three false-color images, from left, depict the density of cesium atoms in a superfluid (conducting) state, in a transition state and finally in an insulating state. The original sample consisted of a single-layer of cesium atoms that formed a sheet measuring 80 microns in diameter, barely visible to the naked eye. Green indicates the lowest density of atoms. Red indicates a high, constant density. Physicists call this a plateau, which University of Chicago scientists have observed for the first time.