Physics Today

Researchers Can Now Vary the Atomic Interactions in a Bose–Einstein Condensate

Barbara Goss Levi

Published Aug 1, 2000• 3 citations

Abstract

Bose–Einstein condensates (BECs) were formed five years ago from rubidium-87 and sodium atoms, whose interactions are repulsive. BECs were also formed from lithium-7 atoms, which attract one another. (See the article by Wolfgang Ketterle in PHYSICS TODAY, December 1999, page 30.) Now researchers in Boulder, Colorado, have created a single condensate of rubidium-85 atoms, which can be taken continuously from the repulsive to the attractive regimes. The experimenters can vary the strength of the interaction between the atoms in their condensate by a factor of 100 or more—and even flip its sign—by changing the external magnetic field. The ability to tune the interactions of a condensate opens the door to systematic explorations of atomic behavior in new regimes.

DOI: 10.1063/1.1310115

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