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arXiv · 0808.0026

Determination of the Superfluid Gap in Atomic Fermi Gases by Quasiparticle Spectroscopy

Andre Schirotzek·Yong-il Shin·Christian H. Schunck·Wolfgang Ketterle
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Abstract

We present majority and minority radiofrequency (RF) spectra of strongly interacting imbalanced Fermi gases of Li-6. We observed a smooth evolution in the nature of pairing correlations from pairing in the superfluid region to polaron binding in the highly polarized normal region. The imbalance induces quasiparticles in the superfluid region even at very low temperature. This leads to a local bimodal spectral response, which allows us to determine the superfluid gap Δand the Hartree energy U.

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Andre Schirotzek, Yong-il Shin, Christian H. Schunck, Wolfgang Ketterle. 2008-08-13. Determination of the Superfluid Gap in Atomic Fermi Gases by Quasiparticle Spectroscopy. https://doi.org/10.1103/physrevlett.101.140403

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