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Functional renormalization group for d-wave superconductivity in Hubbard type models

H. C. Krahl·C. Wetterich
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Abstract

The temperature dependence of d-wave superconducting order for two dimensional fermions with d-wave attraction is investigated by means of the functional renormalization group with partial bosonization. Below the critical temperature T_c we find superconductivity, a gap in the electron propagator and a temperature dependent anomalous dimension. At T_c the renormalized "superfluid density" jumps and the approach to T_c from above is characterized by essential scaling. These features are characteristic for a phase transition of the Kosterlitz-Thouless (KT) type.

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H. C. Krahl, C. Wetterich. 2008-01-28. Functional renormalization group for d-wave superconductivity in Hubbard type models. https://doi.org/10.1016/j.physleta.2007.03.028

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