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arXiv · 1311.4229

Functional renormalization group approach to conventional theory of superfluidity and beyond

Yuya Tanizaki·Gergely Fejős·Tetsuo Hatsuda
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Abstract

Fermionic functional renormalization group (FRG) is applied to describe the superfluid phase transition of the two-component fermionic system with attractive contact interaction. Connection between the fermionic FRG approach and the Bardeen-Cooper-Schrieffer (BCS) theory with its Gorkov and Melik-Barkhudarov (GMB) correction is made clear, and the FRG flow of the fermion self-energy is also studied to go beyond the BCS+GMB theory. The superfluid transition temperature and the associated chemical potential are calculated in the region of the negative scattering length using fermionic FRG.

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Yuya Tanizaki, Gergely Fejős, Tetsuo Hatsuda. 2013-11-17. Functional renormalization group approach to conventional theory of superfluidity and beyond. https://doi.org/10.1088/1742-6596/529/1/012027

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