Probing a Bose-Einstein condensate with an atom laser

D Döring,J D Close,C Figl,N P Robins

doi:10.1364/oe.16.013893

Abstract

A pulsed atom laser derived from a Bose-Einstein condensate is used to probe a second target condensate. The target condensate scatters the incident atom laser pulse. From the spatial distribution of scattered atoms, one can infer important properties of the target condensate and its interaction with the probe pulse. As an example, we measure the s-wave scattering length that, in low energy collisions, describes the interaction between the |F = 1,m(F) = -1) and |F = 2,m(F) = 0) hyperfine ground states in (87)Rb.

Highlights

Since the realization of Bose-Einstein condensation in ultracold atomic gases, the atom laser, a highly coherent, freely propagating beam of low energy atoms has been developed by several groups [1, 2, 3, 4]
We present experimental results and make a comparison to numerical simulations to get a measurement of the s-wave scattering length between the two states involved in the scattering process
The density distribution is dominated by the momentum distribution as opposed to the change in position when the atom laser pulse traverses the target condensate

Summary

Introduction

Since the realization of Bose-Einstein condensation in ultracold atomic gases, the atom laser, a highly coherent, freely propagating beam of low energy atoms has been developed by several groups [1, 2, 3, 4]. To form an atom laser, a beam of atoms is coherently output-coupled from a trapped Bose-Einstein condensate to a state that does not interact with the trapping potential. The atoms fall away from the trap producing a coherent de Broglie matter wave that is the atom laser beam. Atom lasers are the direct analogue of optical lasers. Both devices rely on Bose-enhanced scattering for their operation, and both produce coherent beams derived from a macroscopically populated trapped state. The flux, the spatial mode, the coherence properties and the quantum statistics have all been studied both experimentally and theoretically [5, 6, 7]

Methods

Results

Conclusion