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arXiv · 2105.00086

Full Slonczewski-Weiss-McClure parametrization of few-layer twistronic graphene

Aitor Garcia-Ruiz·Haiyao Deng·Vladimir V. Enaldiev·Vladimir I. Fal'ko
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Abstract

We use a hybrid k dot p theory - tight binding (HkpTB) model to describe interlayer coupling simultaneously in both Bernal and twisted graphene structures. For Bernal-aligned interfaces, HkpTB is parametrized using the full Slonczewski-Weiss-McClure (SWMcC) Hamiltonian of graphite, which is then used to refine the commonly used minimal model for twisted interfaces, by deriving additional terms that reflect all details of the full SWMcC model of graphite. We find that these terms introduce some electron-hole asymmetry in the band structure of twisted bilayers, but in twistronic multilayer graphene, they produce only a subtle change of moire miniband spectra, confirming the broad applicability of the minimal model for implementing the twisted interface coupling in such systems.

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Aitor Garcia-Ruiz, Haiyao Deng, Vladimir V. Enaldiev, Vladimir I. Fal'ko. 2021-04-30. Full Slonczewski-Weiss-McClure parametrization of few-layer twistronic graphene. https://doi.org/10.1103/physrevb.104.085402

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