2018/12/31 by Xiao-Hong Pan, Kai-Jie Yang, Li Chen +3 · 1 citation
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevlett.123.156801
published as Phys. Rev. Lett. 123, 156801 (2019) · 6 pages, 4 figures, updated with the application for bismuthine
arxiv created 2019/05/09 · arxiv updated 2019/10/16
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 locating at the corners for various lattice patterns. In particular, we focus on the 2DTI with D3d 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 lattice symmetry broken. 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.