Seventy years after Albert Einstein built upon the work of Indian physicist S.N. Bose and predicted that gaseous atoms cooled to extreme temperatures would abruptly gather in the lowest possible energy state, physicists finally observed the phenomenon. The discovery and subsequent investigation of this new state of matter—termed the Bose-Einstein condensate (BEC)—has earned Eric A. Cornell, Wolfgang Ketterle and Carl. E. Wieman this year's Nobel Prize in Physics.
According to the Nobel committee, the three scientists "have caused atoms to sing in unison" because atoms in a BEC are all at the same energy and oscillate together, essentially acting as a primitive laser beam comprised of matter instead of light. The 10,000,000 Swedish Crown prize (about $950,000) is shared among the three scientists and will be presented at a ceremony on December 10th.
Eric A. Cornell(below at left), of JILA and the National Institute of Standards and Technology (NIST), and Carl E. Wieman (below center), of JILA and the University of Colorado, Boulder, documented the first ever BEC in 1995. It was comprised of approximately 2,000 rubidium atoms that the researchers cooled to the chilly temperature of 20 nanokelvin—a mere 0.000 000 02 degrees above absolute zero.
Wolfgang Ketterle(below right) of the Massachusetts Institute of Technology used sodium atoms to produce BECs that contained more individual atoms than the first rubidium BEC. By then studying the interaction and interference patterns of two sodium BECs, Ketterle illustrated that the condensate was comprised of completely coordinated atoms.
The article "Trends in Physics: The Coolest Gas in the Universe," by Graham P. Collins (Scientific American, December 2000) is available for purchase from the Scientific American Archive.