Lattice-Symmetry-Assisted Second-Order Topological Superconductors and Majorana Patterns
Lattice-Symmetry-Assisted Second-Order Topological Superconductors and Majorana Patterns
复制标题
晶格对称辅助二阶拓扑超导体和马约拉纳图案
DOI：
10.1103/physrevlett.123.156801
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发表时间：
2019
影响因子：
8.6
通讯作者：
Liu Xin
中科院分区：
文献类型：
--
作者：
Pan Xiao-Hong;Yang Kai-Jie;Chen Li;Xu Gang;Liu Chao-Xing;Liu Xin
我们提出了一种基于二维拓扑绝缘体（2DTI）的具有角马约拉纳零模式（MZM）的晶格对称辅助二阶拓扑超导体的实现。晶格对称性自然会导致沿不同方向的边缘态与面内磁场和传统 s 波配对的各向异性耦合，从而导致位于各种晶格图案拐角处的单个 MZM。特别是，我们关注具有 D-3d 晶格对称性的 2DTI，并在广泛的参数范围内发现了沿扶手椅和锯齿形边缘的边缘态的不同类型的能隙开口。因此，单个 MZM 存在于锯齿形边缘和扶手椅边缘之间的拐角处，并且对于弱破缺晶格对称性具有鲁棒性。我们建议以各种多边形图案（例如三角形和四边形）实现此类角 MZM。我们通过在面内磁场下构建马约拉纳 Y 结，进一步展示了它们在构建马约拉纳网络方面的潜力。
We propose a realization of the lattice-symmetry-assisted second-order topological superconductors with corner Majorana zero modes (MZM) based on two-dimensional topological insulators (2DTI). The lattice symmetry can naturally lead to the anisotropic coupling of edge states along different directions to the in-plane magnetic field and conventional s-wave pairings, thus leading to a single MZM located at the corners for various lattice patterns. In particular, we focus on the 2DTI with D-3d lattice symmetry and found different types of gap opening for the edge states along the armchair and zigzag edges in a broad range of parameters. As a consequence, a single MZM exists at the corner between the zigzag and armchair edges, and is robust against weakly broken lattice symmetry. We propose to realize such corner MZMs in a variety of polygon patterns, such as triangles and quadrilaterals. We further show their potentials in building the Majorana network through constructing the Majorana Y junction under an in-plane magnetic field.