论文标题
封装的双层jacutingaite中的栅极可调失衡的凯恩 - 梅尔模型
Gate-tunable imbalanced Kane-Mele model in encapsulated bilayer jacutingaite
论文作者
论文摘要
我们从第一原则中免费学习，免费和封装的双层jacutingaite pt $ _2 $ hgse $ _3 $。虽然自由立式的双层是一个巨大的缝隙琐碎的绝缘子，但我们发现，由于Sublattice Symmetry Breaking和Sublattice依赖于Sublattice依赖于Sublattice的Next-Neartest Neighbor跳跃，封装的结构具有很小的微不足道差距。在应用小垂直电场时，封装的双层经历了向量子旋转厅绝缘子的拓扑过渡。我们发现，可以通过对两层建模并通过不平衡的凯恩 - 梅勒模型对两层进行建模和描述，从而考虑了sublatice不平衡和每层相应的反转对称性破裂。在这张图片中，双层jacutingaite经历了从0+0状态的过渡，其中每一层都是微不足道的，到0+1状态，其中仅在其中一层中出现了一个异常的拓扑状态。
We study free, capped and encapsulated bilayer jacutingaite Pt$_2$HgSe$_3$ from first principles. While the free standing bilayer is a large gap trivial insulator, we find that the encapsulated structure has a small trivial gap due to the competition between sublattice symmetry breaking and sublattice-dependent next-nearest-neighbor hopping. Upon the application of a small perpendicular electric field, the encapsulated bilayer undergoes a topological transition towards a quantum spin Hall insulator. We find that this topological transition can be qualitatively understood by modeling the two layers as uncoupled and described by an imbalanced Kane-Mele model that takes into account the sublattice imbalance and the corresponding inversion-symmetry breaking in each layer. Within this picture, bilayer jacutingaite undergoes a transition from a 0+0 state, where each layer is trivial, to a 0+1 state, where an unusual topological state relying on Rashba-like spin orbit coupling emerges in only one of the layers.
