Ultrafast charge dynamics and photoluminescence in bilayer MoS₂

Our examination of the interplay ultrafast charge dynamics and electron-phonon interaction in bilayer MoS2 provides a microscopic basis for understanding features (two peaks) emission spectrum. We demonstrate that while initial accumulation excited occurs at near Q point two-dimensional Brillioun zone, takes place predominantly through two pathways: direct recombination K indirect phonon-assisted electrons valley holes {\Gamma} hill Brillouin zone. Analysis wave vector dependencies traces higher energy peak to relaxation from conduction band. results thus reveal importance photoemissive properties few-layer transition-metal dichalcogenide. These calculations are based on time dependent density functional theory matrix formulation.