MANY-BODY EFFECTS IN THE ELECTROMODULATION SPECTRA OF MODULATION-DOPED QUANTUM-WELLS - THEORY AND EXPERIMENT

We have performed a theoretical (first-principles) and experimental (contactless electroreflectance) investigation of the temperature dependence (17<T<351 K) of the electric-field-modulated interband; transitions in a pseudomorphic Ga(0.81)Al(0.l9)AS/In0.20Ga0.80As/GaAs modulation-doped quantum-well that contains a two-dimensional electron gas. We find that many-body effects are a factor at all temperatures although they are most pronounced for T less than or equal to 152 K. Because of the derivativelike nature of our approach, both theoretical and experimental, the weak Fermi-edge transition is still visible up to at least 152 K, as a complement to the results of previous theoretical and experimental investigations.