论文标题
堆叠顺序与Chern索引之间的一般关系：微型双层石墨烯的拓扑图
A general relation between stacking order and Chern index: a topological map of minimally twisted bilayer graphene
论文作者
论文摘要
我们得出了描述两层双层石墨烯和Chern索引的相对移位的堆叠矢量$ {\ bf u} $之间的一般关系。我们发现$ c =ν-\ text {sign} \ left（| v_ {ab} | - | | v_ {ba} | \右）$，其中$ν$是valley索引，$ | v_ {αβ} | $ actacking势值的绝对价值取决于$ {\ bf u} $ conterection interection in Interique in Interame Interame In Inique in Inique; AA堆叠在拓扑特征中没有任何作用。通过这种表达，我们表明，尽管理想和放松的微型双层石墨烯似乎是如此独特，以至于几乎是不同的材料，但其Chern索引图非常相同。因此，该材料的拓扑物理学对晶格松弛非常强大。
We derive a general relation between the stacking vector ${\bf u}$ describing the relative shift of two layers of bilayer graphene and the Chern index. We find $C = ν- \text{sign}\left(|V_{AB}|-|V_{BA}|\right)$, where $ν$ is a valley index and $|V_{αβ}|$ the absolute value of stacking potentials that depend on ${\bf u}$ and that uniquely determine the interlayer interaction; AA stacking plays no role in the topological character. With this expression we show that while ideal and relaxed minimally twisted bilayer graphene appear so distinct as to be almost different materials, their Chern index maps are, remarkably, identical. The topological physics of this material is thus strongly robust to lattice relaxations.
