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Anderson–Bogoliubov Collective Excitations in Superfluid Fermi Gases at Nonzero Temperatures

  • S. N. Klimin
  • H. Kurkjian
  • J. TempereEmail author
Article
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Abstract

The Anderson–Bogoliubov branch of collective excitations in a condensed Fermi gas is treated using the effective bosonic action of Gaussian pair fluctuations. The spectra of collective excitations are treated for finite temperature and momentum throughout the BCS–BEC crossover. The obtained spectra explain, both qualitatively and quantitatively, recent experimental results on Goldstone modes in atomic Fermi superfluids.

Keywords

Ultracold Fermi gases Collective excitations Anderson–Bogoliubov mode 

Notes

Acknowledgements

The present work is supported by the University Research Fund (BOF) of the University of Antwerp and by the Flemish Research Foundation (FWO-Vl), Project No. G.0429.15.N and the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant Agreement No. 665501.

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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.TQCUniversiteit AntwerpenAntwerpBelgium
  2. 2.Lyman Laboratory of PhysicsHarvard UniversityCambridgeUSA

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