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arXiv · 0809.2145

Bragg spectroscopy of a strongly interacting Fermi gas

G. Veeravalli·E. Kuhnle·P. Dyke·C. J. Vale
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Abstract

We present a comprehensive study of the Bose-Einstein condensate to Bardeen-Cooper-Schrieffer (BEC-BCS) crossover in fermionic $^6$Li using Bragg spectroscopy. A smooth transition from molecular to atomic spectra is observed with a clear signature of pairing at and above unitarity. These spectra probe the dynamic and static structure factors of the gas and provide a direct link to two-body correlations. We have characterised these correlations and measured their density dependence across the broad Feshbach resonance at 834 G.

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G. Veeravalli, E. Kuhnle, P. Dyke, C. J. Vale. 2008-12-22. Bragg spectroscopy of a strongly interacting Fermi gas. https://doi.org/10.1103/physrevlett.101.250403

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