Photoluminescence excitation spectra in GaAs/AlAs trench-buried quantum wires with 20 nm wide rectangular cross-sectional shapes

Polarization-dependent photoluminescence excitation spectra (PLE) are measured in GaAs/AlAs rectangular trench-buried quantum wires (QWRs) with 20 nm width and various thicknesses. Experiments demonstrate that the polarization properties of the PLE spectra, which have several clear peaks corresponding to the optical transitions between quantized conduction and valence subbands, significantly depend on the cross-sectional ratios of the rectangular wires. Quantum indices of these transition levels are assigned by comparing the experiments with theory. The distinctive optical features of the QWRs with the rectangular cross sections are discussed in relation to the characteristics of one-dimensional valence subbands. (C) 1996 American Institute of Physics.