In the 1995 JILA experiment, what state of matter was created from ultracold rubidium atoms?

In the 1995 JILA experiment, a Bose–Einstein condensate was created from ultracold rubidium atoms.

Eric Cornell and Carl Wieman, working at JILA with colleagues, cooled rubidium-87 atoms to temperatures only a tiny fraction above absolute zero. They used laser cooling, magnetic trapping, and evaporative cooling to reduce the atoms’ motion.

At sufficiently low temperature, many bosons occupy the same lowest-energy quantum state. The atoms then behave collectively as a coherent matter wave rather than as independent particles. This new state was the Bose–Einstein condensate predicted by Satyendra Nath Bose and Albert Einstein decades earlier.

The achievement was distinct from superfluid helium, another quantum state of matter. Cornell, Wieman, and Wolfgang Ketterle shared the 2001 Nobel Prize in Physics for work on Bose–Einstein condensation.