Theory of exciton formation and relaxation in quantum wires

Abstract

The relaxation dynamics of electron-hole pairs generated by a short laser pulse near the band edge of a GaAs quantum wire is analyzed by using a microscopic density matrix approach. We account for Coulomb renormalizations of various scattering mechanisms that are of importance near the band gap. The exciton formation dynamics, photoluminescence signals, and the build-up of center-of-mass kinetic energies depend crucially on the excitation energy. Exciton formation and dissociation are shown to change characteristically with temperature.