LEVEL BROADENING EFFECTS IN QUANTUM KINETIC-EQUATIONS - HOT LUMINESCENCE FROM A QUANTUM-WIRE NEAR THE OPTICAL-PHONON-EMISSION THRESHOLD

We consider the quantum kinetic equations in a spatially homogeneous s ituation for cases in which only level shift and broadening are of imp ortance, while coherence phenomena can be neglected. In this case we c an formulate the quantum kinetic equations in a form similar to semicl assical Boltzmann rate equations. We also consider a specific problem: Hot luminescence from a quantum wire near the threshold for optical-p honon emission. The problem is first discussed within the framework of the Boltzmann equation. After pointing out the failure of this descri ption, the Boltzmann equations are generalized to a set of quantum kin etic equations, which in turn an solved in order to describe the lumin escence spectra.