Phase correlations and quasicondensate in a two-dimensional ultracold Fermi gas
arXiv:1407.5474 · doi:10.1016/j.jmmm.2014.07.050
Abstract
The interplay between dimensionality, coherence and interaction in superfluid Fermi gases is analyzed by the phase correlation function of the field of fermionic pairs. We calculate this phase correlation function for a two-dimensional superfluid Fermi gas with -wave interactions within the Gaussian pair fluctuation formalism. The spatial behavior of the correlation function is shown to exhibit a rapid (exponential) decay at short distances and a characteristic algebraic decay at large distances, with an exponent matching that expected from Berezinskii-Kosterlitz-Thouless theory of 2D Bose superfluids. We conclude that the Gaussian pair fluctuation approximation is able to capture the physics of quasi long-range order in two-dimensional Fermi gases.
14 pages, 4 figures, accepted in Journal of Magnetism and Magnetic Materials
References in corpus (7)
- Many-Body Physics with Ultracold Gases
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- Strongly Interacting Two-Dimensional Bose Gases
- The effect of population imbalance on the Berezinskii-Kosterlitz-Thouless phase transition in a superfluid Fermi gas
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