Quantization of photo-excited carriers in GaAs doping superlattices

Photo-excited carriers in periodic doping multilayer structures of GaAs are studied using resonant inelastic light scattering techniques. Spin-flip single-particle intersubband excitations clearly demonstrate the quantization of electrons in purely space-charge induced potential wells. With increasing excitation intensity the electric subbands broaden to minibands with considerable dispersion with k perpendicular to the layers. A quasi-three-dimensional behavior is found in both self-consistent calculations and electronic Raman scattering experiments.