BoseEinstein condensate
From Wikipedia, the free encyclopedia.
A BoseEinstein condensate is a gaseous superfluid phase formed by atoms cooled to temperatures very near to absolute zero. The first such condensate was produced by Eric Cornell and Carl Wieman in 1995 at the University of Colorado at Boulder, using a gas of rubidium atoms cooled to 170 nanokelvins (nK). Under such conditions, a large fraction of the atoms collapse into the lowest quantum state, producing a superfluid.
Contents 
Theory
The collapse of the atoms into a single quantum state is known as Bose condensation or BoseEinstein condensation. This phenomenon was predicted in the 1920s by Satyendra Nath Bose and Albert Einstein, based on Bose's work on the statistical mechanics of photons, which was then formalized and generalized by Einstein. The result of the efforts of Bose and Einstein is the concept of a Bose gas, governed by the BoseEinstein statistics, which describes the statistical distribution of certain types of identical particles now known as bosons. Bosonic particles, which include the photon as well as atoms such as helium4, are allowed to share quantum states with each other. Einstein speculated that cooling bosonic atoms to a very low temperature would cause them to fall (or "condense") into the lowest accessible quantum state, resulting in a new form of matter.
The critical temperature (in a uniform threedimensional gas consisting of particles with no apparent internal degrees of freedom, and with no or uniform external potential) at which this happens can be derived to be:
where:

T_{c} is the critical temperature, n the particle density, m the mass per boson, h Planck's constant, k_{B} the Boltzmann constant, and ζ the Riemann zeta function; ζ(3 / 2) ≈ 2.6124.
See also
 Electromagnetically induced transparency
 Slow glass
 Gravastar
 Superfluid
 Supersolid
 Superheavy atom
 TonksGirardeau gas
 Gas in a box
 Bose gas
 Fermionic condensate
External links
 Nobel Prize in Physics 2001  for the achievement of BoseEinstein condensation in dilute gases of alkali atoms, and for early fundamental studies of the properties of the condensates
 BoseEinstein Condensates at JILA
 Atom Optics at UQ
 Europhysics News Report on Slowed Light
 Einstein's manuscript on the BoseEinstein condensate discovered at Leiden University
 BoseEinstein Condensation of Helium and Hydrogen inside Bundles of Carbon Nanotubes
References
 S. N. Bose, Z. Phys. 26, 178 (1924)
 A. Einstein, Sitz. Ber. Preuss. Akad. Wiss. (Berlin) 22, 261 (1924)
 L.D. Landau, J. Phys. USSR 5, 71 (1941)
 L. Landau (1941). Theory of the Superfluidity of Helium II, Physical Review, 60: 356358
 M.H. Anderson, J.R. Ensher, M.R. Matthews, C.E. Wieman, and E.A. Cornell (1995). Observation of BoseEinstein Condensation in a Dilute Atomic Vapor, Science, 269: 198201
 D. S. Jin, J. R. Ensher, M. R. Matthews, C. E. Wieman, and E. A. Cornell (1996). Collective Excitations of a BoseEinstein Condensate in a Dilute Gas, Physical Review Letters, 77: 420423
 M. R. Matthews, B. P. Anderson, P. C. Haljan, D. S. Hall, C. E. Wieman, and E. A. Cornell (1999). Vortices in a BoseEinstein Condensate, Physical Review Letters, 83: 24982501
 S. Jochim, M. Bartenstein, A. Altmeyer, G. Hendl, S. Riedl, C. Chin, J. Hecker Denschlag, and R. Grimm (2003). BoseEinstein Condensation of Molecules, Science, 302: 21012103
 Markus Greiner, Cindy A. Regal and Deborah S. Jin (2003). Emergence of a molecular Bose−Einstein condensate from a Fermi gas, Nature, 426: 537540
 M. W. Zwierlein, C. A. Stan, C. H. Schunck, S. M. F. Raupach, S. Gupta, Z. Hadzibabic, and W. Ketterle (2003). Observation of BoseEinstein Condensation of Molecules, Physical Review Letters, 91: 250401
 C. J. Pethick and H. Smith, "BoseEinstein Condensation in Dilute Gases", Cambridge University Press, Cambridge, 2004.
Phases of matter 

Solid  Amorphous solid  Liquid  Gas  Gel  Plasma  Superfluid  Supersolid  Degenerate matter  Neutronium  Quarkgluon plasma  Fermionic condensate  BoseEinstein condensate  Strange matter 