INELASTIC LIGHT-SCATTERING BY ELECTRONS IN GAAS QUANTUM WIRES - SPIN-DENSITY, CHARGE-DENSITY AND SINGLE-PARTICLE EXCITATIONS

In inelastic light scattering experiments we observe for the first tim e clearly resolved one dimensional (1D) intersubband spin-density exci tations. Together with new structure at energies close to the 2D inter subband transitions, these observations display the formation of 1D su bbands. The depolarization shift (W(dep)) and the excitonic shift (W(x c)) can be deduced approximately from our experiments. These shifts ar e of special interest because they are related to the direct and excha nge-correlation terms of the electron-electron interaction. We find ra tios of the shifts (W(xc)/W(dep)) of up to 55%.