Abstract
Pronounced many-body exciton effects have been observed through photoluminescence in modulation-doped n-type GaAs quantum wells where a near-resonance coincidence exists between a transition involving two-dimensional electrons at the Fermi level in the first conduction subband and an exciton transition from the second conduction subband. Under these conditions, strong and distinct Fermi-edge singularities can be observed near k≊0. A magnetic field induces further enhancement of the effect but also leads to very large, -periodic amplitude variations in the photoluminescence, with excursions over 3 orders of magnitude.
- Received 4 January 1991
DOI:https://doi.org/10.1103/PhysRevB.43.14738
©1991 American Physical Society