• 文献标题:   Quantum spin Hall phase in multilayer graphene
  • 文献类型:   Article
  • 作  者:   GARCIAMARTINEZ NA, LADO JL, FERNANDEZROSSIER J
  • 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:   Int Iberian Nanotechnol Lab INL
  • 被引频次:   3
  • DOI:   10.1103/PhysRevB.91.235451
  • 出版年:   2015

▎ 摘  要

The so-called quantum spin Hall phase is a topologically nontrivial insulating phase that is predicted to appear in graphene and graphenelike systems. In this paper we address the question of whether this topological property persists in multilayered systems. We consider two situations: purely multilayer graphene and heterostructures where graphene is encapsulated by trivial insulators with a strong spin-orbit coupling. We use a four-orbital tight-binding model that includes full atomic spin-orbit coupling and we calculate the Z(2) topological invariant of the bulk states as well as the edge states of semi-infinite crystals with armchair termination. For homogeneous multilayers we find that even when the spin-orbit interaction opens a gap for all possible stackings, only thosewith an odd number of layers host gapless edge states while those with an even number of layers are trivial insulators. For heterostructures where graphene is encapsulated by trivial insulators, it turns out that interlayer coupling is able to induce a topological gap whose size is controlled by the spin-orbit coupling of the encapsulatingmaterials, indicating that the quantum spin Hall phase can be induced by proximity to trivial insulators.