Two-dimensional higher-order topology in monolayer graphdiyne
| Autor: | Lee, Eunwoo, Kim, Rokyeon, Ahn, Junyeong, Yang, Bohm-Jung |
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| Rok vydání: | 2019 |
| Předmět: | |
| Zdroj: | npj Quantum Materials 5, 1 (2020) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1038/s41535-019-0206-8 |
| Popis: | Based on first-principles calculations and tight-binding model analysis, we propose monolayer graphdiyne as a candidate material for a two-dimensional higher-order topological insulator protected by inversion symmetry. Despite the absence of chiral symmetry, the higher-order topology of monolayer graphdiyne is manifested in the filling anomaly and charge accumulation at two corners. Although its low energy band structure can be properly described by the tight-binding Hamiltonian constructed by using only the $p_z$ orbital of each atom, the corresponding bulk band topology is trivial. The nontrivial bulk topology can be correctly captured only when the contribution from the core levels derived from $p_{x,y}$ and $s$ orbitals are included, which is further confirmed by the Wilson loop calculations. We also show that the higher-order band topology of a monolayer graphdyine gives rise to the nontrivial band topology of the corresponding three-dimensional material, ABC-stacked graphdiyne, which hosts monopole nodal lines and hinge states. Comment: 19 pages, 4 figures, new title |
| Databáze: | arXiv |
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