Commensurate and incommensurate double moire interference in graphene encapsulated by hexagonal boron nitride. (15th May 2020)

• Record Type: Journal Article
• Authors: Leconte, N; Jung, J
• Is Part Of: 2D materials. Volume 7:Number 3(2020)
• Publication Date: 2020-05-15
• Subjects: graphene -- boron nitride -- double moire -- supermoire -- moire bands -- encapsulated graphene -- moire superlattice; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/ab891a
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: Interference of double moire patterns of graphene (G) encapsulated by hexagonal boron nitride (BN) can alter the electronic structure features near the primary/secondary Dirac points and the electron-hole symmetry introduced by a single G/BN moire pattern depending on the relative stacking arrangements of the top/bottom BN layers. We show that strong interference effects are found in nearly aligned BN/G/BN and BN/G/NB and obtain the evolution of the associated density of states as a function of moire superlattice twist angles. For equal moire periods and commensurate patterns with Δ φ = 0° modulo 60° moire angle differences the patterns can add up constructively leading to large pseudogaps of about ∼ 50 meV on the hole side or cancel out destructively depending on their relative sliding, e.g. partially recovering electron-hole symmetry. The electronic structure of moire quasicrystals for Δ φ = 30° differences reveal double moire features in the density of states with almost isolated van Hove singularities where we can expect strong correlations.