Abstract
Local density fluctuations and density profiles of a Fermi gas are measured in situ and analyzed. In the quantum degenerate regime, the weakly interacting gas shows a suppression of the density fluctuations compared to the nondegenerate case, where atomic shot noise is observed. This manifestation of antibunching is a direct result of the Pauli principle and constitutes a local probe of quantum degeneracy. We analyze our data using the predictions of the fluctuation-dissipation theorem and the local density approximation, demonstrating a fluctuation-based temperature measurement.
- Received 30 April 2010
DOI:https://doi.org/10.1103/PhysRevLett.105.040401
©2010 American Physical Society
Viewpoint
Suppressed fluctuations in Fermi gases
Published 19 July 2010
Sometimes experimental noise is actually signal. Two groups have shown how density fluctuations in a gas of identical fermions can be used as a nanokelvin thermometer.
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