The Rashba4 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.
@article{arxiv.2310.02001,
title = {Triplet superconductivity in the Rashba$^4$ model},
author = {G. A. H. Schober and M. Salmhofer},
journal= {arXiv preprint arXiv:2310.02001},
year = {2023}
}