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arXiv · 2309.00825

Magic momenta and three dimensional Landau levels from a three dimensional graphite moiré superlattice

Xin Lu·Bo Xie·Yue Yang·Xiao Kong·Jun Li·Feng Ding·Zhu-Jun Wang·Jianpeng Liu
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Abstract

Twisted bilayer graphene (TBG) and other quasi-two-dimensional moiré superlattices have attracted significant attention due to the emergence of various correlated and topological states associated with the flat bands in these systems. In this work, we theoretically explore the physical properties of a new type of \textit{three dimensional graphite moiré superlattice}, the bulk alternating twisted graphite (ATG) system with homogeneous twist angle, which is grown by in situ chemical vapor decomposition method. Compared to TBG, the bulk ATG system is bestowed with an additional wavevector degrees of freedom due to the extra dimensionality. As a result, we find that when the twist angle of bulk ATG is smaller than twice of the magic angle of TBG, there always exist ``magic momenta" at which the in-plane Fermi velocities of the moiré bands vanish. Moreover, topologically distinct flat bands of TBG at different magic angles can even co-exist at different out-of-plane wavevectors in a single bulk ATG system. Most saliently, when the twist angle is relatively large, exactly dispersionless three dimensional zeroth Landau level would emerge in the bulk ATG, which may give rise to robust three dimensional quantum Hall effects over a large range of twist angles.

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Xin Lu, Bo Xie, Yue Yang, Xiao Kong, Jun Li, Feng Ding, Zhu-Jun Wang, Jianpeng Liu. 2023-09-02. Magic momenta and three dimensional Landau levels from a three dimensional graphite moiré superlattice. https://doi.org/10.1103/physrevlett.132.056601

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