Carrier-carrier and carrier-phonon scattering in the low-density and low-temperature regime for resonantly pumped semiconductor quantum dots

Abstract

We study carrier relaxation due to Coulomb scattering and interaction with LO-phonons in semiconductor quantum dots at low temperatures. Scattering for different relaxation process are evaluated for various carrier distributions that correspond to stages of the typical relaxation kinetics after optical excitation with a weak pulse, generating on average less than one electron per quantum dot. Even when the spacing of the quantum dot energy levels does not match the LO-phonon energy, we find that carrier-LO-phonon scattering, in addition to electronelectron and electron-hole interaction, provides efficient carrier relaxation. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.