Richard Schmidt

Certain materials, near absolute zero, superconduct: electricity flows without loss. The critical temperature starts this. John Bardeen and colleagues explained that atomic vibrations glue electrons into Cooper pairs.

A lone potassium atom enters a dense cloud of sodium atoms cooled to near absolute zero. Such a medium is called a Bose–Einstein condensate — all particles merge into a single quantum wave. One might expect the impurity to simply pick up a single neighbor and form a pair. But the experiment showed something else.