Band structure of twisted bilayer graphene on hexagonal boron nitride

Tommaso Cea, Pierre A. Pantaleon, Francisco Guinea

备注：: 7+10 pages; main text + supplementary information
发表信息：: Phys. Rev. B 102, 155136 (2020)
DOI：: 10.1103/PhysRevB.102.155136

英文摘要：

The effect of an hexagonal boron nitride (hBN) layer close aligned with twisted bilayer graphene (TBG) is studied. At sufficiently low angles between twisted bilayer graphene and hBN, $θ_{hBN} \lesssim 2^\circ$, the graphene electronic structure is strongly disturbed. The width of the low energy peak in the density of states changes from $W \sim 5 - 10$ meV for a decoupled system to $\sim 20 - 30$ meV. Spikes in the density of states due to van Hove singularities are smoothed out. We find that for a realistic combination of the twist angle in the TBG and the twist angle between the hBN and the graphene layer the system can be described using a single moiré unit cell.

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