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Particle correlations in a fermi superfluid

Austen Lamacraft
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Abstract

We discuss correlations between particles of different momentum in a superfluid fermi gas, accessible through noise measurements of absorption images of the expanded gas. We include two elements missing from the simplest treatment, based on the BCS wavefunction: the explicit use of a conserving approximation satisfying particle number conservation, and the inclusion of the contribution from Cooper pairs at finite momentum. We expect the latter to be a significant issue in the strongly correlated state emerging in the BCS-BEC crossover.

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Austen Lamacraft. 2007-04-30. Particle correlations in a fermi superfluid. https://doi.org/10.1103/physreva.73.011602

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