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arXiv · 2310.02001

Triplet superconductivity in the Rashba$^4$ model

G. A. H. Schober·M. Salmhofer
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Abstract

The Rashba$^4$ model is a lattice model of interacting fermions with a tight-binding dispersion relation that exhibits four Rashba band crossing points at the same energy. The fermions interact weakly, by an on-site repulsion and an additional nearest-neighbour two-body interaction, which may be attractive or repulsive. We study this model when the Fermi energy is at or close to the band crossings, by a combination of renormalization group flow equations and mean-field theory. We find that the scattering processes between different Rashba points drive superconductivity of an unusual triplet type not found in models with a single Rashba point.

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G. A. H. Schober, M. Salmhofer. 2023-10-03. Triplet superconductivity in the Rashba$^4$ model. https://arxiv.org/abs/2310.02001

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