Abstract
The low-energy modes of a superfluid atomic Fermi gas at zero temperature are investigated. The Bose-Einstein-condensate (BEC) side of the superfluid phase is studied in detail. The atoms are assumed to be in only one internal state, so that for a sufficiently diluted gas the pairing of fermions can be considered effective in the l = 1 channel only. In agreement with previous works on p-wave superfluidity in Fermi systems, it is found that the p x + i p y phase represents the lowest energy state in both the Bardeen-Cooper-Schrieffer (BCS) and BEC sides. Our calculations show that at low energy three branches of collective modes can emerge, with different species of dispersion relations: a phonon-like mode, a single-particle-like mode and a gapped mode. A comparison with the Bogoliubov excitations of the corresponding spinor Bose condensate is made. They reproduce the dispersion relations of the excitation modes of the p-wave superfluid Fermi gas to a high accuracy.
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Matera, F., Wagner, M. Collective modes of p-wave superfluid Fermi gases in BEC phase. Eur. Phys. J. D 69, 158 (2015). https://doi.org/10.1140/epjd/e2015-60131-7
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DOI: https://doi.org/10.1140/epjd/e2015-60131-7