Nayak AK, Reiner J, Queiroz R, Fu H, Shekhar C, Yan B, Felser C, Avraham N, Beidenkopf H (2019)
Publication Type: Journal article
Publication year: 2019
Book Volume: 5
Article Number: eaax6996
Journal Issue: 11
The growing diversity of topological classes leads to ambiguity between classes that share similar boundary phenomenology. This is the status of bulk bismuth. Recent studies have classified it as either a strong or a higher-order topological insulator, both of which host helical modes on their boundaries. We resolve the topological classification of bismuth by spectroscopically mapping the response of its boundary modes to a screw-dislocation. We find that the one-dimensional mode, on step-edges, extends over a wide energy range and does not open a gap near the screw-dislocations. This signifies that this mode binds to the screw-dislocation, as expected for a material with nonzero weak indices. We argue that the small energy gap, at the time reversal invariant momentum L, positions bismuth within the critical region of a topological phase transition between a higher-order topological insulator and a strong topological insulator with nonzero weak indices.
APA:
Nayak, A.K., Reiner, J., Queiroz, R., Fu, H., Shekhar, C., Yan, B.,... Beidenkopf, H. (2019). Resolving the topological classification of bismuth with topological defects. Science Advances, 5(11). https://doi.org/10.1126/sciadv.aax6996
MLA:
Nayak, Abhay Kumar, et al. "Resolving the topological classification of bismuth with topological defects." Science Advances 5.11 (2019).
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