Consiglio, A. (2024) Excitons at room temperature in a two-dimensional quantum spin Hall insulator. Il nuovo cimento C, 47 (5). pp. 1-6. ISSN 1826-9885
|
Text
ncc13062.pdf - Published Version Download (1MB) | Preview |
Abstract
Both experimental techniques and theoretical methods based on density functional theory, ab-initio GW, and Bethe-Salpeter equation calculations have been employed to investigate optical resonances in the quantum spin Hall (QSH) insulator Bismuthene (a honeycomb layer of bismuth atoms) grown on a Silicon Carbide substrate. This material exhibits a direct gap of 1.3 eV at the K and K’ points, making it an excellent candidate for studying excitons in the visible and near-infrared range, even under room temperature conditions. The results, here focused on the theoretical aspects, confirm that the strong electron-hole interaction indeed has a significant impact on the optical excitations, and provide the first evidence of excitons in a 2D QSH insulator. Two main excitonic transitions are observed, with the lowest peak embedded in the single-particle direct gap, featuring a binding energy of ∼ 0.15 eV. Furthermore it is noteworthy that, in this material, both excitonic and topological features stem from the same electronic structure.
| Item Type: | Article |
|---|---|
| Subjects: | 500 Scienze naturali e Matematica > 530 Fisica |
| Depositing User: | Marina Spanti |
| Date Deposited: | 09 Dec 2024 13:40 |
| Last Modified: | 09 Dec 2024 13:40 |
| URI: | http://eprints.bice.rm.cnr.it/id/eprint/23266 |
Actions (login required)
 |
View Item |
