Constrained random phase approximation of the effective Coulomb interaction in lattice models of twisted bilayer graphene

@article{Vanhala2020ConstrainedRP,
  title={Constrained random phase approximation of the effective Coulomb interaction in lattice models of twisted bilayer graphene},
  author={Tuomas I. Vanhala and Lode Pollet},
  journal={Physical Review B},
  year={2020},
  volume={102},
  pages={035154}
}
Recent experiments on twisted bilayer graphene show the urgent need for establishing a low-energy lattice model for the system. We use the constrained random phase approximation to study the interaction parameters of such models, taking into account screening from the moir\'e bands left outside the model space. Based on an atomic-scale tight-binding model, we numerically compute the polarization function and study its behavior for different twist angles. We discuss an approximation scheme which… Expand
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