Exciton-phonon coupling and luminescence: Difference between revisions
No edit summary |
No edit summary |
||
| Line 15: | Line 15: | ||
Also, we assume that you already know how to run both a basic Yambo GW-BSE calculation and a DFPT phonon calculation with Quantum ESPRESSO. | Also, we assume that you already know how to run both a basic Yambo GW-BSE calculation and a DFPT phonon calculation with Quantum ESPRESSO. | ||
Besides the QE executables <source lang=" | Besides the QE executables <source lang="bash" enclose="none">pw.x</source> and `ph.x`, we also use the yambo phonon-specific executable `yambo_ph` and the python utility `yambopy`. The auxiliary code LetzElPhC (executable `lelphc`) will be used to obtain the electron-phonon matrix elements by reading the same electronic wavefunctions used by Yambo (and stored in the `SAVE` directory), while also making full use of crystal symmetries. LetzElPhC (link) will be run by Yambopy, but it must nonetheless be installed. Finally, the exciton-phonon properties can be computed either using `yambo_ph` or using Yambopy itself. | ||
== References == | == References == | ||
Revision as of 10:42, 18 September 2025
In this advanced tutorial, we will calculate exciton-phonon interactions from first principles by interfacing DFPT (for phonon calculations) and BSE (for exciton calculations).
The DFTP calculations are run with Quantum ESPRESSO, while the many-body GW-BSE calculations are run with Yambo. Finally, the exciton-phonon interaction will be obtained by combining and postprocessing the databases computed in the two previous runs. The great advantage of this workflow is that the calculations can be run in the irreducible Brillouin zones both for the electronic momenta ($k$) and the transfer momenta ($Q$, $q$) of excitons and phonons, thus speeding up considerably the jobs while reducing the IO and memory load.
We will first compute the exciton-phonon coupling matrix elements: these are the building blocks needed to construct experimental observables such as phonon-assisted optical spectra (such as luminescence), Raman spectra and exciton lifetimes. We will do this in the case of monolayer MoS2, a 2D system with large spin-orbit interaction.
As an example of application, we will consider the case of phonon-assisted luminescence. We will do this in the case of bulk hBN, a layered indirect insulator with strong electron-phonon coupling.
Note: this tutorial will be updated when new exc-ph tools become available in Yambopy (including full-python postprocessing, Raman spectra, interpolated lifetimes, etc).
This is an advanced topic: we assume that you already know something about the theory[1][2][3][4][5][6] and applications[7][8][9][10][11][12][13] of exciton-phonon physics.
Also, we assume that you already know how to run both a basic Yambo GW-BSE calculation and a DFPT phonon calculation with Quantum ESPRESSO.
Besides the QE executables <source lang="bash" enclose="none">pw.x</source> and `ph.x`, we also use the yambo phonon-specific executable `yambo_ph` and the python utility `yambopy`. The auxiliary code LetzElPhC (executable `lelphc`) will be used to obtain the electron-phonon matrix elements by reading the same electronic wavefunctions used by Yambo (and stored in the `SAVE` directory), while also making full use of crystal symmetries. LetzElPhC (link) will be run by Yambopy, but it must nonetheless be installed. Finally, the exciton-phonon properties can be computed either using `yambo_ph` or using Yambopy itself.
References
- ↑ Optical processes in solids, Toyozawa, Yutaka, and Chris Oxlade. Cambridge University Press, (2003).
- ↑ [First-principles description of the exciton-phonon interaction: A cumulant approach], P. Cudazzo, Phys. Rev. B, 102, 045136 (2020)
- ↑ Theory of exciton-phonon coupling, G. Antonius, S. G. Louie, Phys. Rev. B, 105, 085111 (2022)
- ↑ Exciton-phonon interaction calls for a revision of the “exciton” concept, F. Paleari, A. Marini, Phys. Rev. B, 106, 125403 (2022)
- ↑ First-principles approaches to the description of indirect absorption and luminescence spectroscopy: exciton-phonon coupling in hexagonal boron nitride, PhD thesis, Fulvio Paleari (2019)
- ↑ Exciton-phonon coupling and phonon-assisted luminescence in hexagonal Boron Nitride nanostructures, PhD Thesis, Pierre Lechifflart (2023)
- ↑ Distinguishing different stackings in layered materials via luminescence spectroscopy, M. Zanfrognini et al. Phys. Rev. Lett. 131, 206902 (2023)
- ↑ First-principles study of luminescence in hexagonal boron nitride single layer: Exciton-phonon coupling and the role of substrate, P Lechifflart, F Paleari, D Sangalli, C Attaccalite Phys. Rev. M, 7 (2), 024006 (2023)
- ↑ Exciton Lifetime and Optical Line Width Profile via Exciton–Phonon Interactions: Theory and First-Principles Calculations for Monolayer MoS2, Y-h Chan, J. B. Haber, M. H. Naik, J. B. Neaton, D. Y. Qiu, F. H. da Jornada, S. G. Louie, Nano Lett., 23, 9 (2023)
- ↑ Origin of Interlayer Exciton–Phonon Coupling in 2D Heterostructures, M. Nalabothula, S. Reichardt, L. Wirtz, Nano Lett., 25, 15 (2025)
- ↑ Exciton-Phonon Interaction and Relaxation Times from First Principles, Hsiao-Yi Chen, Davide Sangalli, and Marco Bernardi, Phys. Rev. Lett. 125, 107401(2020)
- ↑ Exciton-Phonon Coupling in the Ultraviolet Absorption and Emission Spectra of Bulk Hexagonal Boron Nitride, F. Paleari et al. PRL 122, 187401(2019)
- ↑ Theory of phonon-assisted luminescence in solids: Application to hexagonal boron nitride, E. Cannuccia, B. Monserrat and C. Attaccalite, Phys. Rev. B 99, 081109(R) (2019)
Cite error: <ref> tag with name "marini_g" defined in <references> is not used in prior text.