Bose-Einstein Condensation

It’s pretty cool

Where it all began

• (1924) Indian S.N. Bose derives the Planck law for black-body by treating photons as a gas of identical particles

• Einstein later generalizes Bose’s theory, for an ideal gas of identical molecules

• Lead to the prediction of a new form of matter

Bose

Einstein

A bit of an explanation

• As the temperature is lowered the molecules of the gas collapse into the ground state

• In the lowest energy state the molecules blur together and form the Condensate

• So, Bose-Einstein condensate is just a collection of identical atoms smeared together in the lowest quantum-energy state

• Although the prediction had been around since the 1920’s, it wasn’t realized until 1995 by Eric Cornell and Carl Weiman of Colorado University

The formation BEC from left to right

How do we make it?• Well, we cool some gas…• This is actually harder to

do than it sounds: the gas must be cooled down to a few microKelvin, or less

• It must also be kept Isolated from its surroundings

• In a typical Cooling apparatus there are four main sections– Vacuum Pump– Trap– Laser Cooling System– Evaporative Cooling

System

Strange Properties

• Superfluid• Optically Dense• Magnetically

Hypersensitive• Laser-like: Coherent

matter waves• Solitons

• Fermionic-Condensate• Bosenova

Bose-nova

Super-nova

That’s Neat, but What is it good for?

• Bose-Einstein Condensate is still, for the most part in its infancy.

• Despite this, there have been few tentative ideas about applications of BEC

• Those few that have been formed stem from BEC’s extreme sensitivity to its environment

• The only immediate reward for study of BEC is to further our understanding of Quantum Physics

• There is hope for the future though: BEC bears a striking resemblance to the early laser

That’s all…for now

• BEC-a new form of matter which is achieved when enough atoms of a gas are trapped together at the ground-state energy level

• Great Experimental potential: it could be quite some time before we’ve explored all the facets of this interesting condensate

• While you won’t be buying any BEC-based products in the near future, you’ll probably be hearing more about it as research continues…

References

http://www.wikipedia.orghttp://www.colorado.edu/physics/2000/index.plhttp://www.mpq.mpg.de/qdynamics/projects/bec/bec.htmlhttp://www.physorg.com/news6303.htmlhttp://www.exn.ca/dailyplanet/story.asp?id=2002011152http://www-lplgb.univ-paris13.fr/Gb/Equipes/GroupeCOMETA/

GroupeCOMETA.htmhttp://physicsweb.org/articles/world/10/3/3http://www.light-science.com/phys2.htmlhttp://physics.nist.gov/Pubs/Bec/TofCont.html

Thanks to Phil for help with my pictures