• 文献标题:   Curvature-tuned electronic properties of bilayer graphene in an effective four-dimensional spacetime
  • 文献类型:   Article
  • 作  者:   CARIGLIA M, GIAMBO R, PERALI A
  • 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:   Univ Fed Ouro Preto
  • 被引频次:   4
  • DOI:   10.1103/PhysRevB.95.245426
  • 出版年:   2017

▎ 摘  要

We show that in AB stacked bilayer graphene low-energy excitations around the semimetallic points are described by massless, four-dimensional Dirac fermions. There is an effective reconstruction of the four-dimensional spacetime, including in particular the dimension perpendicular to the sheet, that arises dynamically from the physical graphene sheet and the interactions experienced by the carriers. The effective spacetime is the Eisenhart-Duval lift of the dynamics experienced by Galilei invariant Levy-Leblond spin-1/2 particles near the Dirac points. We find that changing the intrinsic curvature of the bilayer sheet induces a change in the energy level of the electronic bands, switching from a conducting regime for negative curvature to an insulating one when curvature is positive. In particular, curving graphene bilayers allow opening or closing the energy gap between conduction and valence bands, a key effect for electronic devices. Thus, using curvature as a tunable parameter opens the way for the beginning of curvatronics in bilayer graphene.