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arXiv · 2010.15633

Chiral Majorana Hinge Modes in Superconducting Dirac Materials

Bo Fu·Zi-Ang Hu·Chang-An Li·Jian Li·Shun-Qing Shen
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Abstract

Chiral Majorana hinge modes are characteristic of a second-order topological superconductor in three dimensions. Here we systematically study pairing symmetry in the point group D_{2h}, and find that the leading pairing channels can be of s-, d-, and s+id-wave pairing in Dirac materials. Except for the odd-parity s-wave pairing superconductivity, the s+id-wave pairing superconductor 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. Our findings suggest the strong spin-orbital coupling, crystalline symmetries and electron-electron interaction in the Dirac materials may provide a microscopic mechanism to realize chiral Majorana hinge modes without utilizing the proximity effect or external fields.

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Bo Fu, Zi-Ang Hu, Chang-An Li, Jian Li, Shun-Qing Shen. 2020-10-29. Chiral Majorana Hinge Modes in Superconducting Dirac Materials. https://doi.org/10.1103/physrevb.103.l180504

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