Fang Chen, Gilbert Matthew J, Bernevig B Andrei
Department of Physics, University of Illinois, Urbana, Illinois 61801-3080, USA and Micro and Nanotechnology Laboratory, University of Illinois, Urbana, Illinois 61801, USA and Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
Department of Electrical and Computer Engineering, University of Illinois, Urbana, Illinois 61801, USA and Micro and Nanotechnology Laboratory, University of Illinois, Urbana, Illinois 61801, USA.
Phys Rev Lett. 2014 Mar 14;112(10):106401. doi: 10.1103/PhysRevLett.112.106401. Epub 2014 Mar 10.
We study a new type of three-dimensional topological superconductor that exhibits Majorana zero modes (MZM) protected by a magnetic group symmetry, a combined antiunitary symmetry composed of a mirror reflection and time reversal. This new symmetry enhances the noninteracting topological classification of a superconducting vortex from Z2 to Z, indicating that multiple MZMs can coexist at the end of one magnetic vortex of unit flux. Especially, we show that a vortex binding two MZMs can be realized on the (001) surface of a topological crystalline insulator SnTe with proximity induced BCS Cooper pairing, or in bulk superconductor InxSn1-xTe.
我们研究了一种新型的三维拓扑超导体,它展现出由磁群对称性保护的马约拉纳零模(MZM),这种对称性是由镜面反射和时间反演组成的复合反幺正对称性。这种新对称性将超导涡旋的非相互作用拓扑分类从Z2增强到Z,这表明在单位磁通的一个磁涡旋末端可以共存多个MZM。特别地,我们表明在具有近邻诱导BCS库珀对的拓扑晶体绝缘体SnTe的(001)表面上,或者在体超导体InxSn1-xTe中,可以实现束缚两个MZM的涡旋。