INELASTIC LIGHT-SCATTERING BY THE 2-DIMENSIONAL ELECTRON-GAS - FRACTIONAL QUANTUM HALL REGIME AND BEYOND

Mechanisms of resonant inelastic light scattering by the electron gas are evaluated here for their impact in the current research of semicon ductor nanostructures. Recent experiments in the fractonal quantum Hal l regime highlight the power of the resonant inelastic light-scatterin g method in studies of electron electron interactions in semiconductor s of reduced dimensions. These applications follow from its capabiliti es to measure spin-density and charge-density collective modes as well as excitations that are not predicted by conventional response functi ons of the electron gas. We consider measurements of intersubband exci tations of two-dimensional systems in GaAs quantum wells and observati ons of gap excitations in the fractional quantum Hall effect.