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Probing the quantum state of a guided atom laser pulse

Kevin L. Moore·Subhadeep Gupta·Kater W. Murch·Dan M. Stamper-Kurn
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Abstract

We describe bichromatic superradiant pump-probe spectroscopy as a tomographic probe of the Wigner function of a dispersing particle beam. We employed this technique to characterize the quantum state of an ultracold atomic beam, derived from a Rb-87 Bose-Einstein condensate, as it propagated in a 2.5 mm diameter circular waveguide. Our measurements place an upper bound on the longitudinal phase-space area occupied by the 300,000 atom beam of 9(1) $\hbar$ and a lower bound on the coherence length (L > 13 microns). These results are consistent with full quantum degeneracy after multiple orbits around the waveguide.

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Kevin L. Moore, Subhadeep Gupta, Kater W. Murch, Dan M. Stamper-Kurn. 2006-06-07. Probing the quantum state of a guided atom laser pulse. https://doi.org/10.1103/physrevlett.97.180410

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