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Aephraim Steinberg(and the web!)
Ultracold atoms andBose-Einstein
condensation…
How scientists brag...
(Does this mean much? If so, what? And who picked the key words?)
Play your own games at the Web of Science or INSPEC(http://isi6.isiknowledge.com/portal.cgi/WOS et al via www.library.utoronto.ca/resources/)
HISTORYPrehistory: Fermions vs Bosons (Bose & Einstein, 1924-5)
periodic table versus laserparticle versus wave?
1930s: London… superfluidity due to BEC?…superconductivity too?
1976: Stwalley/Noganow: spin-polarized H?1980s: Silvera/Walraven, Hess, Kleppner,…
Evaporative coolingParallel: Development of laser cooling1988: Anomalously low temperatures!
The race is on…1995: BEC in Rb, Na, almost Li (a<0!)…1996: Nobel prize -- for Helium 3!1997: Nobel prize -- for laser cooling!2001: Nobel prize -- for BEC, at long last.now: the interesting stuff!
See: http://www.nobel.se (Nobel homepage)and http://physicsweb.org/articles/world/10/3/3and http://www.colorado.edu/physics/2000/bec/and http://cua.mit.edu/ketterle_group/ and so on...
Phase diagram of just about anything…
"If it were really impossible, why would they bother to forbid it?"(Eric Cornell paraphrasing Joseph Heller)
HOW COLD MUST YOU GET?
Need 1 atom per cubic wavelength… wavelength = 1 / momentum… water would needto be near 3 degrees K, but solidifies first (cf He!)
Alkalis solidify too; need densities millions of times lowerthan air: need temperatures less than 1 uK!
In particular: get atoms within 1 optical wavelength ofeach other, and keep their momentum < photon's.
Laser cooling alone can't do it (understood by mid 90s);steal "evaporative cooling" idea from Hydrogen crowd.
RF cooling, a la Ketterle (MIT)
Number of atoms in ground state, vs temperature:A quantum phase transition.
The third group to get there?
What would you do?
Thirty-five new reports of laboratory observations of BEC in atomic gases have come in since May, 1997:
July 11, 2002: Hold the phone! July 3, 2002: First in China June 28, 2002: Home of the whopper April 8, 2002: Formula One in Oxford December 21, 2001: Japan 4 December 12, 2001: BEC am Bodensee! November 21, 2001: Rubidium at NIST Gaithersburg October 31, 2001: Special K June 19, 2001: German Micro BEC at Tübingen May 18, 2001: Vive la difference! May 17, 2001: Strine debut May 11, 2001: Optical route through Georgia March 12, 2001: Grail in sight in Holy Land! February 23, 2001: Helium work is really hopping in France! February 16, 2001: He has arrived! January 31, 2001: It's freezing in Paris-Nord July 21, 2000: Third Japanese condensate November 21, 1999: A Pisa the action July, 1999: Dutch Treat June 23, 1999: New Rubidium Gelato Taste Treat March 29, 1999: The Game's Afoot in Oxford December 30, 1998: Now Kyoto December 16, 1998: Sweet Sixteen in the Land of the Rising Sun September 22, 1998: Cool Brittania August 25, 1998: A First in the Southern Hemisphere August 5, 1998: Lucky Number in Hannover July 8, 1998: BEC in 87Rb - a new Aspect June 24, 1998: H at Last ! May 11, 1998: Report from École Normale Supérieure February 26, 1998: BEC at NIST Gaithersburg January 23, 1998: Bavarian Breakthrough ! September 30, 1997: Now playing in Europe July 10, 1997: Stanford group weighs in July 2, 1997: BEC observed at the Rowland Institute May 20, 1997: BEC observed at the University of Texas
Close to 100 BEC's by 2005.
2 in 19950 in 19964 in 199710 in 1998...12 in 2001 .....
(How many do we need?)
Competing to build the "atom laser"…
Interference with Atoms!
QuickTime™ and aGIF decompressorare needed to see this picture.
Games with vortices in BEC
Nonlinear atom optics…
Best gravimeters/accelerometers?
Quantum computers (can getwell-controlled atoms to interactwith each other)?
Model system to understandsolid-state problems (high-Tcsuperconductivity etc)?
The next-generation atomic clock
QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.
QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.
(Actually, this generation!)