Including Excitonic Effects in Phonon-Mediated Relaxation in Semiconductor Nanocrystals

Accounting for the electron-hole bound state effects is necessary for an accurate description of dynamics of photo-excited semiconductor nanomaterials. Here, we use density function theory (DFT) simulation output to solve the Bethe-Salpeter equation (BSE) for singlet excitons and incorporate the BSE results for exciton states into the existing technique for phonon-mediated relaxation in nanomaterials based on reduced density matrix and Redfield theory. This results in a method that includes excitonic effects. As an application, we compute photoluminescence (PL) spectrum in several semiconductor nanocrystals.