Double Majorana vortex zero modes in superconducting topological crystalline insulators with surface rotation anomaly
Double Majorana vortex zero modes in superconducting topological crystalline insulators with surface rotation anomaly
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DOI：
10.1103/physrevb.102.180505
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发表时间：
2020-11-20
影响因子：
3.7
通讯作者：
Furusaki, Akira
中科院分区：
文献类型：
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作者：
Kobayashi, Shingo;Furusaki, Akira
已知时间反演和n重旋转对称性（n = 2，4，6）的相互作用带来了一类新的拓扑晶体绝缘体（TCI），其由于表面旋转异常而具有n个表面狄拉克锥。结果表明，这些超导体表面的邻近诱导s波超导性产生了一个拓扑超导相，其中两个Majorana零模被束缚在一个涡旋上，n重旋转对称性（n = 2，4，6）丰富了超导涡旋的拓扑分类，从Z（2）到Z（2）× Z（2）.利用具有s波超导性和二重旋转对称性的三维高自旋拓扑绝缘体模型，通过两个拓扑涡旋相变，我们证明了随着化学势的增加，涡旋一端的Majorana零模数目按2 -> 1 -> 0的方式变化.此外，我们发现，额外的磁镜对称性进一步增强了拓扑分类Z x Z。
The interplay of time-reversal and n-fold rotation symmetries (n = 2, 4, 6) is known to bring a new class of topological crystalline insulators (TCIs) having n surface Dirac cones due to a surface rotation anomaly. We show that the proximity-induced s-wave superconductivity on the surface of these TCIs yields a topological superconducting phase in which two Majorana zero modes are bound to a vortex, and that n-fold rotation symmetry (n = 2, 4, 6) enriches the topological classification of a superconducting vortex from Z(2) to Z(2) x Z(2). Using a model of a three-dimensional high-spin topological insulator with s-wave superconductivity and twofold rotation symmetry, we show that, with increasing chemical potential, the number of Majorana zero modes at one end of a vortex changes as 2 -> 1 -> 0 through two topological vortex phase transitions. In addition, we show that additional magnetic-mirror symmetry further enhances the topological classification to Z x Z.