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arXiv · 1308.5487

Local observation of pair-condensation in a Fermi gas at unitarity

M. G. Lingham·K. Fenech·S. Hoinka·C. J. Vale
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Abstract

We present measurements of the local (homogeneous) density-density response function of a Fermi gas at unitarity using spatially resolved Bragg spectroscopy. By analyzing the Bragg response across one axis of the cloud we extract the response function for a uniform gas which shows a clear signature of the Bose-Einstein condensation of pairs of fermions when the local temperature drops below the superfluid transition temperature. The method we use for local measurement generalizes a scheme for obtaining the local pressure in a harmonically trapped cloud from the line density and can be adapted to provide any homogeneous parameter satisfying the local density approximation.

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M. G. Lingham, K. Fenech, S. Hoinka, C. J. Vale. 2014-03-19. Local observation of pair-condensation in a Fermi gas at unitarity. https://doi.org/10.1103/physrevlett.112.100404

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