• 文献标题:   Hofstadter butterfly and the quantum Hall effect in twisted double bilayer graphene
  • 文献类型:   Article
  • 作  者:   CROSSE JA, NAKATSUJI N, KOSHINO M, MOON P
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:   New York Univ Shanghai
  • 被引频次:   0
  • DOI:   10.1103/PhysRevB.102.035421
  • 出版年:   2020

▎ 摘  要

We study the energy spectrum and quantum Hall effects of the twisted double bilayer graphene in uniform magnetic field. We investigate two different arrangements, AB-AB and AB-BA, which differ in the relative orientation but have very similar band structures in the absence of a magnetic field. For each system we calculate the energy spectrum and quantized Hall conductivities at each spectral gap by using a continuum Hamiltonian that satisfies the magnetotranslation condition. We show that the Hofstadter butterfly spectra of AB-AB and AB-BA stackings differ significantly, even though their zero magnetic field band structures closely resemble; the spectrum of AB-AB has valley degeneracy, which can be lifted by applying interlayer potential asymmetry, while the spectrum of AB-BA has no such degeneracy in any case. We explain the origin of the difference from the perspectives of lattice symmetry and band topology.