Physicists cool particles to less than a billionth of a degree above absolute zero to probe quantum magnetism

The experiment constitutes the coldest temperature in the universe.

An artist’s conception of the complex magnetic correlations physicists have observed with a groundbreaking quantum simulator at Kyoto University that uses ytterbium atoms about 3 billion times colder than deep space. Different colors represent the six possible spin states of each atom. Credit: Ella Maru Studio/Courtesy of K. Hazzard/Rice University.