Flat-band-induced non-Fermi-liquid behavior of multicomponent fermions

@article{Kumar2021FlatbandinducedNB,
  title={Flat-band-induced non-Fermi-liquid behavior of multicomponent fermions},
  author={Pramod Kumar and Sebastiano Peotta and Yosuke Takasu and Yoshiro Takahashi and P{\"a}ivi T{\"o}rm{\"a}},
  journal={Physical Review A},
  year={2021}
}
We investigate multicomponent fermions in a flat band and predict experimental signatures of non-Fermi-liquid behavior. We use dynamical mean-field theory to obtain the density, double occupancy and entropy in a Lieb lattice for $\mathcal{N}=2$ and $\mathcal{N}=4$ components. We derive a mean-field scaling relation between the results for different values of $\mathcal{N}$, and study its breakdown due to beyond mean-field effects. The predicted signatures occur at temperatures above the N\'eel… 
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