English

Coulomb interactions in systems of generalized semi-Dirac fermions

Strongly Correlated Electrons 2025-07-11 v3 Mesoscale and Nanoscale Physics Materials Science

Abstract

Interactions have strong effects in systems with flat bands. We examine the role of Coulomb interactions in two dimensional chiral anisotropic quasiparticles that disperse linearly in one direction and have relatively flat bands near the neutrality point in the other direction, dispersing with an arbitrary positive even power law 2n22n\geq2. As in the conventional semi-Dirac case (n=1(n=1), we show using renormalization group that strong logarithmic divergences in the self-energy of generalized semi-Dirac fermions resum and lead to a restoration of linearity in the spectrum for arbitrary nn over a sizable energy window in the perturbative regime. We discuss those results in light of previous non-perturbative large NfN_{f} results and address the implications for physical observables.

Keywords

Cite

@article{arxiv.2410.22572,
  title  = {Coulomb interactions in systems of generalized semi-Dirac fermions},
  author = {Mohamed M. Elsayed and Bruno Uchoa and Valeri N. Kotov},
  journal= {arXiv preprint arXiv:2410.22572},
  year   = {2025}
}

Comments

11 pages, 6 figures