MOMENTUM CONSERVATION IN THE LUMINESCENCE OF MODULATION-DOPED GAXIN1-XAS-ALYIN1-YAS QUANTUM-WELLS

The k-conserving selection rule in the electron-hole recombination is investigated by intensity-dependent photoluminescence measurements in n-type modulation-doped GaxIn1-xAs-AlyIn1-yAs single quantum wells intentionally doped with Be acceptors in the well centre. The k-non-conserving recombination process involves electrons with momentum up to the Fermi edge and holes localized on the Be acceptors. The transition from a one-component electron plasma to a two-component electron-hole plasma is studied by comparing the experimental results with theoretical line shape models. The density-dependent band gap renormalization is determined for the one-component and the two-component electron-hole plasma. The obtained results are found to agree well with recent theoretical calculations.