Tri-Dirac surface modes in topological superconductors

We propose a new type of topological surface modes having cubic dispersion in three-dimensional topological superconductors. Lower order dispersions are prohibited by the threefold rotational symmetry and time-reversal symmetry. Cooper pairing in the bulk changes sign under improper rotations, akin...

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Bibliographic Details
Main Authors: Fang, Chen, Bernevig, B. Andrei, Gilbert, Matthew J.
Other Authors: Massachusetts Institute of Technology. Department of Physics
Format: Article
Language:English
Published: American Physical Society 2015
Online Access:http://hdl.handle.net/1721.1/96720
https://orcid.org/0000-0002-9236-7410
Description
Summary:We propose a new type of topological surface modes having cubic dispersion in three-dimensional topological superconductors. Lower order dispersions are prohibited by the threefold rotational symmetry and time-reversal symmetry. Cooper pairing in the bulk changes sign under improper rotations, akin to [superscript 3]He-B. The surface manifestations are a divergent surface density of states at the Fermi level and isospins that rotate three times as they circle the origin in momentum space. We propose that Heusler alloys with band inversion are candidate materials to harbor the novel topological superconductivity.