dc voltage effect on elementary excitations of a two-dimensional electron gas

Using a generalized self-consistent field theory we obtained the intersubband spectra of charge-density excitations for the nonuniform electron gas of a GaAs-AlxGa1-xAs single quantum well submitted to dc gate voltages. The simulations performed with incoming laser light in extreme resonance conditions with the split-off gap of the GaAs demonstrate the collective character of the single-particle excitations and the different regimes of coupling between the charge-density excitations and the longitudinal optical phonon of GaAs.