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arXiv · 1908.08439

Electronic structure of 30° twisted double bilayer graphene

Guodong Yu·Zewen Wu·Zhen Zhan·Mikhail I. Katsnelson·Shengjun Yuan
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Abstract

In this paper, the electronic properties of 30° twisted double bilayer graphene, which loses the translational symmetry due to the incommensurate twist angle, are studied by means of the tight-binding approximation. We demonstrate the interlayer decoupling in the low-energy region from various electronic properties, such as the density of states, effective band structure, optical conductivity and Landau level spectrum. However, at Q points, the interlayer coupling results in the appearance of new Van Hove singularities in the density of states, new peaks in the optical conductivity and importantly the 12-fold-symmetry-like electronic states. The k-space tight-binding method is adopted to explain this phenomenon. The electronic states at Q points show the charge distribution patterns more complex than the 30° twisted bilayer graphene due to the symmetry decrease. These phenomena appear also in the 30° twisted interface between graphene monolayer and AB stacked bilayer.

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Guodong Yu, Zewen Wu, Zhen Zhan, Mikhail I. Katsnelson, Shengjun Yuan. 2020-05-10. Electronic structure of 30° twisted double bilayer graphene. https://doi.org/10.1103/physrevb.102.115123

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