Tight-binding model for the band dispersion in rhombohedral topological insulators over the whole Brillouin zone
| Autor: | Adalberto Fazzio, Matheus P. Lima, Antônio J. R. da Silva, Caio H. Lewenkopf, Carlos Mera Acosta |
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| Rok vydání: | 2018 |
| Předmět: |
Physics
Condensed Matter - Mesoscale and Nanoscale Physics Condensed matter physics Dirac (software) FOS: Physical sciences 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Brillouin zone Tight binding Atomic orbital Topological insulator Mesoscale and Nanoscale Physics (cond-mat.mes-hall) 0103 physical sciences 010306 general physics 0210 nano-technology Electronic band structure Energy (signal processing) Surface states |
| Zdroj: | Physical Review B. 98 |
| ISSN: | 2469-9969 2469-9950 |
| DOI: | 10.1103/physrevb.98.035106 |
| Popis: | We put forward a tight-binding model for rhombohedral topological insulator materials with the space group ${D}_{3d}^{5}(R\overline{3}m)$. The model describes the bulk band structure of these materials over the whole Brillouin zone. Within this framework, we also describe the topological nature of surface states, characterized by a Dirac conelike dispersion and the emergence of surface projected bulk states near to the Dirac point in energy. We find that the breaking of the ${R}_{3}$ symmetry as one moves away from the $\mathrm{\ensuremath{\Gamma}}$ point has an important role in the hybridization of the ${p}_{x}, {p}_{y}$, and ${p}_{z}$ atomic orbitals. In our tight-binding model, the latter leads to a band mixing matrix element ruled by a single parameter. We show that our model gives a good description of the strategies/mechanisms proposed in the literature to eliminate and/or energy shift the bulk states away from the Dirac point, such as stacking faults and the introduction of an external applied electric field. |
| Databáze: | OpenAIRE |
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