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arXiv · 2309.03416

Topological Mixed Valence Model in Magic-Angle Twisted Bilayer Graphene

Yantao Li·Benjamin M. Fregoso·Maxim Dzero
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Abstract

We develop a model to describe the mixed valence regime in magic-angle twisted bilayer graphene (MATBG) using the recently developed heavy-fermion framework. By employing the large-$N$ slave-boson approach, we derive the self-consistent mean field equations and solve them numerically. We find that the SU(8) symmetry constraint moir\'e system exhibits novel mixed-valence properties which are different from conventional heavy-fermions systems. We find the solutions describing the physics at the filling near the Mott insulator regime in the limit of strong Coulomb interactions between the flat-band fermions. Our model can provide additional insight into the possible microscopic origin of unconventional superconductivity in MATBG.

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Yantao Li, Benjamin M. Fregoso, Maxim Dzero. 2023-09-07. Topological Mixed Valence Model in Magic-Angle Twisted Bilayer Graphene. https://doi.org/10.1103/physrevb.110.045123

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