Exciton-phonon coupling effects on the optical properties of semiconductors: an ab...
| Full text | |
| Author(s): |
Villegas, Cesar E. P.
;
Rodin, A. S.
;
Carvalho, Alexandra
;
Rocha, A. R.
Total Authors: 4
|
| Document type: | Journal article |
| Source: | Physical Chemistry Chemical Physics; v. 18, n. 40, p. 27829-27836, OCT 28 2016. |
| Web of Science Citations: | 13 |
| Abstract | |
Excitons play a key role in technological applications since they have a strong influence on determining the efficiency of photovoltaic devices. Recently, it has been shown that the allotropes of phosphorus possess an optical band gap that can be tuned over a wide range of values including the near-infrared and visible spectra, which would make them promising candidates for optoelectronic applications. In this work we carry out ab initio many-body perturbation theory calculations to study the excitonic effects on the optical properties of two-dimensional phosphorus allotropes: the case of blue and black monolayers. We elucidate the most relevant optical transitions, exciton binding energy spectrum as well as real-space exciton distribution, particularly focusing on the absorption spectrum dependence on the incident light polarization. In addition, based on our results, we use a set of effective hydrogenic models, in which the electron-hole Coulomb interaction is included to estimate exciton binding energies and radii. Our results show an excellent agreement between the many-body methodology and the effective models. (AU) | |
| FAPESP's process: | 12/24227-1 - Optical properties ánd charge-transfer process studies for efficient organic photovoltaic cells: ab-initio simulations |
| Grantee: | César Enrique Pérez Villegas |
| Support type: | Scholarships in Brazil - Post-Doctorate |
| FAPESP's process: | 15/14899-0 - Exciton-phonon coupling effects on the optical properties of semiconductors: an ab-initio density functional theory approach |
| Grantee: | César Enrique Pérez Villegas |
| Support type: | Scholarships abroad - Research Internship - Post-doctor |
| FAPESP's process: | 11/11973-4 - ICTP South American Institute for Fundamental Research: a regional center for theoretical physics |
| Grantee: | Nathan Jacob Berkovits |
| Support type: | Research Projects - Thematic Grants |