Functional renormalization for the Bardeen-Cooper-Schrieffer to Bose-Einstein condensation crossover

• Verfasst von: Scherer, Michael [VerfasserIn]
• Verfasst von: Flörchinger, Stefan [VerfasserIn]
• Verfasst von: Gies, Holger [VerfasserIn]
• Titel: Functional renormalization for the Bardeen-Cooper-Schrieffer to Bose-Einstein condensation crossover
• Verf.angabe: Michael M. Scherer, Stefan Floerchinger and Holger Gies
• E-Jahr: 2011
• Jahr: 13 July 2011
• Umfang: 21 S.
• Fussnoten: Gesehen am 10.10.2022
• Titel Quelle: Enthalten in: Royal Society (London)Philosophical transactions of the Royal Society of London / A
• Ort Quelle: London : Royal Society, 1990
• Jahr Quelle: 2011
• Band/Heft Quelle: 369(2011), 1946, Seite 2779-2799
• ISSN Quelle: 1471-2962
• DOI: doi:10.1098/rsta.2011.0072
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Bardeen-Cooper-Schrieffer to Bose-Einstein condensation crossover
• Sach-SW: functional renormalization group
• Sach-SW: ultracold fermionic atoms
• K10plus-PPN: 1818317265

Abstract

We review the functional renormalization group (RG) approach to the Bardeen-Cooper-Schrieffer to Bose-Einstein condensation (BCS-BEC) crossover for an ultracold gas of fermionic atoms. Formulated in terms of a scale-dependent effective action, the functional RG interpolates continuously between the atomic or molecular microphysics and the macroscopic physics on large length scales. We concentrate on the discussion of the phase diagram as a function of the scattering length and the temperature, which is a paradigm example for the non-perturbative power of the functional RG. A systematic derivative expansion provides for both a description of the many-body physics and its expected universal features as well as an accurate account of the few-body physics and the associated BEC and BCS limits.