How to generate BSE basis in the EPC luminescence

[jasonhan0710]

Dear all,

In the tutorial "Exciton-phonon coupling and luminescence https://www.yambo-code.eu/wiki/index.ph ... minescence", there is a detailed instruction about how to calculate the phonon assisted luminescence. However, I am confused about how to generate the BSE basis with "p2y". Shall I do the same process as illustrated in the tutorial "Electron Phonon Coupling https://www.yambo-code.eu/wiki/index.ph ... n_Coupling"? Or is there any special post process should I do to import the QE results to yambo? Thank you!

Best,
Jason

[claudio]

Dear Jason

in order to calculate exciton-phonon matrix elements that are then needed for the luminescence you need:
1) first to calculate electron-phonon coupling matrix elements with QuantumEspresso,
as explained in section
https://www.yambo-code.eu/wiki/index.ph ... x_elements

where you find script for the hBN case.
All the procedure is explained in the tutorial on electron-phonon coupling in details

2) calculate on the same k-grid the Bethe-Saltpeter equation for all momentum Q
as explained in section:
https://www.yambo-code.eu/wiki/index.ph ... e_momentum

than follow the tutorial to mix together electron-phonon and exciton in such a way to get luminescence

best regards
Claudio Attaccalite