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   COLLOQUIUM OF THE LABORATORY FOR COMPUTER DESIGN OF MATERIALS
                   School of Computational Sciences
                           (CSI 898-Sec 001)
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"Superfluid and Laser Analogies with Coherent Matter Waves"

                         Charles Clark
           Electron and Optical Physics Division
National Institute of Standards and Technology, Gaithersburg, MD

     The production of Bose-Einstein condensates (BECs) of
dilute gases, which has now been done in some 40 laboratories
worldwide, has opened up a new class of macroscopic quantum
many-body phenomena for investigation and application, which was 
not widely (if at all) anticipated a decade ago. A typical BEC 
has a density of nanograms per cc at a temperature lower than 
a microkelvin.  This is a medium with a density one hundred 
thousandth that of air, at a pressure 10^-13 that of the 
atmospheres - so tenuous that for most practical purposes it 
can be thought of as an ultrahigh vacuum! Yet the million atoms 
in a BEC are described by a common quantum-mechanical wavefunction,
so the system exhibits remarkable quantum coherence over macroscopic
dimensions.  I will discuss two of aspects of this coherence: vortex
lattice and vortex ring structures, in which BECs exhibit phenomena
analogous to those encountered in superfluid helium and 
superconductors; and the  "atom laser", in which BECs form the 
engine of a device that effects phase-coherent amplification of 
matter waves.

                         Monday , February 23, 2004
                                  4:30 pm
                        Room 206, Science & Tech. I

Refreshments will be served at 4:15 PM.
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Find the schedule at http://www.scs.gmu.edu/lcdm/seminar/schedule.html
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