论文标题
石墨烯堆栈中的狭窄带，静电相互作用和带拓扑
Narrow bands, electrostatic interactions and band topology in graphene stacks
论文作者
论文摘要
超导和绝缘阶段的出现在扭曲的石墨烯双层中建立了良好的，并且在其他石墨烯层的其他排列中也有报道。我们研究了三个这样的安排：在HBN底物上未近的AB双层石墨烯，两个石墨烯双层相对于彼此扭曲，以及一个在HBN底物上堆叠的ABC堆叠的石墨烯三层。在所有情况下，具有不同拓扑的窄带都会发生，从而产生高密度的状态，从而增强了相互作用的作用。我们研究了在自我一致的hartree-fock近似中处理的远程库仑相互作用的效果。我们发现，Fock电势的现场部分强烈改变了电荷中立的带结构。在此处考虑的三种情况下，哈特里部分没有显着改变频带的形状和宽度，与扭曲的双层石墨烯具有这种潜力相反。
The occurrence of superconducting and insulating phases is well-established in twisted graphene bilayers, and they have also been reported in other arrangements of graphene layers. We investigate three such arrangements: untwisted AB bilayer graphene on an hBN substrate, two graphene bilayers twisted with respect to each other, and a single ABC stacked graphene trilayer on an hBN substrate. Narrow bands with different topology occur in all cases, producing a high density of states which enhances the role of interactions. We investigate the effect of the long range Coulomb interaction, treated within the self consistent Hartree-Fock approximation. We find that the on-site part of the Fock potential strongly modifies the band structure at charge neutrality. The Hartree part does not significantly modify the shape and width of the bands in the three cases considered here, in contrast to the effect that such a potential has in twisted bilayer graphene.
