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arXiv · 0705.3858

Tomographic RF Spectroscopy of a Trapped Fermi Gas at Unitarity

Y. Shin·C. H. Schunck·A. Schirotzek·W. Ketterle
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Abstract

We present spatially resolved radio-frequency spectroscopy of a trapped Fermi gas with resonant interactions and observe a spectral gap at low temperatures. The spatial distribution of the spectral response of the trapped gas is obtained using in situ phase-contrast imaging and 3D image reconstruction. At the lowest temperature, the homogeneous rf spectrum shows an asymmetric excitation line shape with a peak at 0.48(4)$ε_F$ with respect to the free atomic line, where $ε_F$ is the local Fermi energy.

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Y. Shin, C. H. Schunck, A. Schirotzek, W. Ketterle. 2007-05-25. Tomographic RF Spectroscopy of a Trapped Fermi Gas at Unitarity. https://doi.org/10.1103/physrevlett.99.090403

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