Electronic excitations in quantum wires and dots

Resonant ineleastic light scattering is used to study collective and single-particle excitations in GaAs/AlGaAs based quantum wires and quantum dots. Interlevel transitions show a significant blue shift with decreasing confinement length. These excitations are dispersionless in dots. In wires both inter- and intrasubband transitions are observed which show the expected broadening and dispersion with increasing in-plane wave vector. The wire structures are tunable by applying a gate voltage. Electronic excitations have been studied in the whole regime From a density modulated 2D electron gas to isolated quantum wires.