This 3D rendering, produced by Rice University researchers, shows a
matter-wave soliton train, a succession of special waves made of self-attracting
ultracold atoms. Each peak in the train is a Bose-Einstein condensate,
a localized collection of atoms cooled to nearly absolute zero temperature.
Solitons are unusual bundles of waves, constrained to move in only one
dimension. Perhaps the most striking feature of solitons is that they
propagate without spreading; ordinary waves spread out and lose their
original shape as they propagate. Solitons have been observed in many
wave phenomena, such as the motion of water waves in narrow canals,
and light pulses in optical fibers. Advanced optical communications
systems employ solitons because ordinary light pulses spread and require
frequent signal boosters. The atom-wave solitons shown in the figure
may someday be useful for an atom laser. (Figure courtesy of Rice University.)
Whereas the Rice researchers studied a train of solitons over a long
time scale, researchers in Europe (Laboratoire Kastler Brossel, Ecole
Normale Superieure, Paris, and the European Laboratory for Non-Linear
Spectroscopy, Milan, Italy) observed and studied single-soliton formation
and propagation over a macroscopic distance of more than one millimeter.
They compared the behavior of their ultracold gas with an ideal gas,
and found good agreement between their experimental observations and
theory.
Reported by: K.E. Strecker, G. Partridge, A.G. Truscott , and R.G.
Hulet, Nature, 9 May 2002;
L. Khaykovich et al., Science
17 May 2002.
Physics
News Update item on this research
Ultracold
Atoms Page at Laboratoire Kastler Brossel
Rice
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