| Autor: |
Gan, L. -Y., Wang, R., Jin, Y. J., Ling, D. B., Zhao, J. Z., Xu, W. P., Liu, J. F., Xu, H. |
| Rok vydání: |
2016 |
| Předmět: |
|
| Zdroj: |
Phys. Chem. Chem. Phys. 2017,19, 7245-7251 |
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1039/C6CP08123A |
| Popis: |
Based on first-principles calculations, we reported that external pressure can induce topological phase transition in alkaline-earth hexaborides, XB6 (X=Ca, Sr, Ba). It was revealed that XB6 is transformed from trivial semiconductors to topological node-line semimetals under moderate pressures when spin-orbit coupling (SOC) is ignored. The band inversion between B px (pz) and py orbitals at X point is responsible for the formation of node-line semimetals. Three node-line rings around X point are protected by the combination of the time-reversal and spatial inversion symmetries, and the drumhead surface bands are obtained in the interiors of the projected node-line rings. When SOC is included, tiny gaps (< 4.8 meV) open at the crossing lines, and the XB6 becomes strong topological insulators with Z2 indices (1;111). As the SOC-induced gap opening is negligible, our findings thus suggest ideal real systems for experimental exploration of the fundamental physics of topological node-line semimetals. |
| Databáze: |
arXiv |
| Externí odkaz: |
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