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arXiv · 1711.06421

Symmetry-protected line nodes and Majorana flat bands in nodal crystalline superconductors

Shingo Kobayashi·Shuntaro Sumita·Youichi Yanase·Masatoshi Sato
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Abstract

Line nodes in the superconducting gap are known to be a source of Majorana flat bands (MFBs) in time-reversal-invariant superconductors (SCs). Here, we extend this relation to all symmetry-protected line nodes where an additional constraint arising from a symmetry of the crystal destabilizes or hides the existence of MFBs. By establishing a one-to-one correspondence between group theoretical and topological classifications, we are able to classify the possible line-node-induced MFBs, including cases with (magnetic) non-symmorphic space groups. Our theoretical analysis reveals a new type of MFB, i.e., MFBs in antiferromagnetic SCs.

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Shingo Kobayashi, Shuntaro Sumita, Youichi Yanase, Masatoshi Sato. 2017-11-17. Symmetry-protected line nodes and Majorana flat bands in nodal crystalline superconductors. https://doi.org/10.1103/physrevb.97.180504

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