Tunable band gap in twisted bilayer graphene
| Autor: | Jiang, Xiu-Cai, Zhao, Yi-Yuan, Zhang, Yu-Zhong |
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| Rok vydání: | 2024 |
| Předmět: | |
| Zdroj: | Physical Review B 105, 115106 (2022) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevB.105.115106 |
| Popis: | At large commensurate angles, twisted bilayer graphene which holds even parity under sublattice exchange exhibits a tiny gap. Here, we point out a way to tune this tiny gap into a large gap. We start from comprehensive understanding of the physical origin of gap opening by density functional theory calculations. We reveal that the effective inter-layer hopping, intra-layer CDW, or inter-layer charge imbalance favors a gap. Then, on the basis of tight-binding calculations, we suggest that a periodic transverse inhomogeneous pressure, which can tune inter-layer hoppings in specific regions of the moi$\rm\acute{r}$e supercell, may open a gap of over $100$~meV, which is further confirmed by first-principles calculations. Our results provide a theoretical guidance for experiments to open a large gap in twisted bilayer graphene. Comment: 9 pages, 9 figures |
| Databáze: | arXiv |
| Externí odkaz: |
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