Abstract
Chiral Majorana hinge modes are characteristic of a second-order topological superconductor in three dimensions. Here we systematically study pairing symmetry and the leading pairing channels in Dirac materials with the point group , and find that the -wave pairing superconductivity may exist as a consequence of competition between - and -wave pairing. The superconducting state is topologically nontrivial and possesses Majorana hinge and surface modes. The chiral Majorana hinge modes can be characterized by a winding number of the quadrupole moment or quantized quadruple moment at the symmetrically invariant point. Possible relevance to superconductivity in is discussed. Our findings suggest the strong spin-orbital coupling, crystalline symmetries, and electron-electron interaction in the Dirac materials may provide a platform to realize chiral Majorana hinge modes with no proximity effect or external fields.
- Received 3 November 2020
- Revised 15 March 2021
- Accepted 30 April 2021
DOI:https://doi.org/10.1103/PhysRevB.103.L180504
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