Rate equations for dot state occupation

Abstract

Abstract Rate equations for electrons in dot states can be used to avoid the assumption that electrons are distributed thermally according to Fermi functions. The equations treat the processes of capture and emission of electrons from and to the wetting layer, and of recombination between conduction and valence dot states. Electron capture and emission are controlled by generation and absorption of phonons, and the rate equations are solved in the steady states for a dot system in equilibrium with a Bose–Einstein phonon energy distribution. At high temperature, when the emission rate to the wetting layer exceeds the recombination rate, a thermal, Fermi electron distribution is established, whereas at low temperature, where the emission rate is very slow compared with the recombination rate, the occupation probability of dot states is independent of their energy. This is the random population regime.