Electron gas in semiconductor multiple quantum wires: Spatially indirect optical transitions

Abstract

In optical experiments with laterally patterned GaAs quantum wells we observe confinement of free carriers to motion in one dimension. Optical recombination of band-gap transitions shows that free electrons and holes are confined in spatially indirect type-II multiple quantum wires. Resonant-inelastic-light-scattering spectra show intersubband excitations of the one-dimensional electron gas. From the optical measurements we obtain the Fermi energy as well as subband spacing and determine the linear free-electron density.