Tight-binding approach to penta-graphene
| Autor: | Stauber, T., Beltrán, J. I., Schliemann, J. |
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| Rok vydání: | 2015 |
| Předmět: | |
| Zdroj: | Sci. Rep. 6, 22672 (2016) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1038/srep22672 |
| Popis: | We introduce an effective tight-binding model to discuss penta-graphene and present an analytical solution. This model only involves the $\pi$-orbitals of the sp$^2$-hybridized carbon atoms and reproduces the two highest valence bands. By introducing energy-dependent hopping elements, originating from the elimination of the sp$^3$-hybridized carbon atoms, also the two lowest conduction bands can be well approximated - but only after the inclusion of a Hubbard onsite interaction as well as of assisted hopping terms. The eigenfunctions can be approximated analytically for the effective model without energy-dependent hopping elements and the optical absorption is discussed. We find large isotropic absorption of up to 24\% for transitions at the $\Gamma$-point, but the general absorption will show a strongly anisotropic behaviour depending on the linear polarization of the incident light. Comment: 9 pages, 4 figures |
| Databáze: | arXiv |
| Externí odkaz: |
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