Two-dimensional topological nodal line semimetal in layered X2Y (X = Ca, Sr, and Ba; Y = As, Sb, and Bi)

Niu C, Buhl PM, Bihlmayer G, Wortmann D, Dai Y, Bluegel S, Mokrousov Y (2017)

Publication Type: Journal article

Publication year: 2017

Journal

Physical Review B American Physical Society

Book Volume: 95

Article Number: 235138

Journal Issue: 23

DOI: 10.1103/PhysRevB.95.235138

Abstract

In topological semimetals the Dirac points can form zero-dimensional and one-dimensional manifolds, as predicted for Dirac/Weyl semimetals and topological nodal line semimetals, respectively. Here, based on first-principles calculations, we predict a topological nodal line semimetal phase in the two-dimensional compounds X2Y (X = Ca, Sr, and Ba; Y = As, Sb, and Bi) in the absence of spin-orbit coupling (SOC) with a band inversion at the M point. A nontrivial Z2 invariant of Z2=1 remains although a tiny gap appears at the nodal line when SOC is included. The mirror symmetry as well as the electrostatic interaction, which can be engineered via strain, are responsible for the nontrivial phase. In addition, the nontrivial phase is further explicitly confirmed via the existence of exotic edge states without and with SOC.

Involved external institutions

Forschungszentrum Jülich / Research Centre Jülich (FZJ) DE Germany (DE) Shandong-University (SDU) CN China (CN)

How to cite

APA:

Niu, C., Buhl, P.M., Bihlmayer, G., Wortmann, D., Dai, Y., Bluegel, S., & Mokrousov, Y. (2017). Two-dimensional topological nodal line semimetal in layered X2Y (X = Ca, Sr, and Ba; Y = As, Sb, and Bi). Physical Review B, 95(23). https://doi.org/10.1103/PhysRevB.95.235138

MLA:

Niu, Chengwang, et al. "Two-dimensional topological nodal line semimetal in layered X2Y (X = Ca, Sr, and Ba; Y = As, Sb, and Bi)." Physical Review B 95.23 (2017).

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