Strongly polarized photoluminescence and electroluminescence spectra have been obtained from strained GaxIn1−xP quantum wire heterostructures grown on (100) oriented, on-axis GaAs substrates by an in situ epitaxial technique. The phenomenon of strain-induced lateral layer ordering has been exploited in order to create lateral superlattices of GaxIn1−xP compositionally modulated in the [110] direction with a modulation period of 96 Å. The previous and subsequent growth of lattice-matched Ga0.51In0.49P ternary alloy epilayers results in the formation of compressively strained quantum wires. Transmission electron microscopy shows the wire cross sections to be ∼48×200 Å. These structures exhibit 77 K photoluminescence spectra at 1.79 eV that are strongly (96%) polarized parallel to the wires due to strain resulting from the lateral compositional modulation. The intensity of this emission depends critically on the polarization of the incident excitation. Electroluminescence spectra from multiple quantum wire light-emitting diodes display anisotropic polarization as well. The energies and optical anisotropies of these luminescence bands are consistent with a simple theoretical analysis.

GaxIn1−xP/Al0.15Ga0.35In0.5P graded-index separate-confinement heterostructure visible laser structures with multiple quantum wire active regions have been formed in situ during gas source molecular beam epitaxy. No regrowths or ex situ fabrication procedures were employed in the formation of the quantum wires. Quantum wires with cross-sectional dimensions of approximately 50×120 Å were routinely achieved with a linear density of 100/μm. Broad area stripe geometry lasers with contact stripe oriented in the [110] and [1̄10] directions exhibited anisotropic threshold current densities varying in ratio by a factor of more than 3.75. Threshold current densities as low as 400 A/cm2 were obtained for lasers with stripes in the [110] direction, perpendicular to the quantum wires. Strong dependence of electroluminescence polarization on stripe direction was also observed.

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