Quantum-Kinetic Effects in the Linear Optical Response of GaAs Quantum Wells

Abstract

We investigate the influence of quantum-kinetic effects on the linear optical properties of GaAs quantum wells. We demonstrate that these effects arising from a non-Markovian treatment of the scattering terms in the semiconductor Bloch equations lead in the linear optical response to a dependence of many-body effects on the energy. A non-Markovian treatment of scattering terms corresponds to a quasi-particle approximation of many-body effects, where they are independent of the energy. We compare both treatments and show that the quasi-particle treatment (i) overestimates both energy shift and broadening of the exciton resonance and (ii) fails to give quantitative description of the excitonic Mott transition with increasing excitation.