Level broadening effects in quantum kinetic equations: Hot luminescence from a quantum wire near the optical phonon emission threshold

TL;DR

This paper develops a quantum kinetic equation framework to accurately describe hot luminescence in quantum wires near optical phonon emission thresholds, overcoming limitations of classical Boltzmann equations.

Contribution

It introduces a generalized quantum kinetic equation considering level broadening, applicable to systems where coherence effects are negligible, and applies it to luminescence in quantum wires.

Findings

Quantum kinetic equations better describe luminescence spectra near phonon emission thresholds.

Classical Boltzmann equations fail to capture certain quantum effects in this regime.

The approach provides a more accurate theoretical tool for quantum wire optical phenomena.

Abstract

A recipe for the generalization of the Boltzmann equation to a quantum kinetic equation is given for cases in which only level shift and broadening are considered, while coherence phenomena can be neglected. We also consider a specific problem: Hot luminescence from a quantum wire near the threshold for optical phonon emission. The problem is first discussed within the framework of the Boltzmann equation. After pointing out the failure of this description, the Boltzmann equations are generalized to a set of quantum kinetic equations, which in turn are solved in order to describe the luminescence spectra.