Title: Matter-wave de-excitation in reduced dimensions

Abstract: Using counter-propagating laser beams, a roughly spherical Bose-Einstein condensate (BEC) can be separated into an array of 2D sheets, with atoms in each plane sharing a single pancake-shaped macroscopic wavefunction. At low temperatures, quantized vibrational motion normal to the 2D planes, which plays a role analogous to an internal degree of freedom, is frozen into the harmonic oscillator ground state, and the degenerate gas is effectively two dimensional. If the condensate is driven to higher vibrational states, it will decay through atom-atom collisions, converting “internal” energy into the kinetic energy of back-to-back atom pairs ejected as distinct outgoing rings in the 2D plane. We have verified that the decay rate is suppressed by the reduced dimensionality, and we predict even greater suppression for an excited 1D (cigar-shaped) condensate. These systems provide matter-wave analogs of inhibited spontaneous emission in cavities and photonic crystals. We describe the theory of confined matter wave de-excitation, recent experimental results, and possible applications from self-stimulating atom lasers to laboratory cosmology.

Submitter: Philip Johnson

Mentor: Carl Williams

Building 221, Room A241, MS 8423

Division: 842 (Atomic Physics)

Laboratory: Physics

Telephone: 301-975-3527

FAX: 301-990-1350

Email: phil.johnson@nist.gov

Sigma Xi member? No.

Category: Physics