Abstract
Quantum wire heterostructures have been grown in situ using gas source molecular beam epitaxy. Lateral composition variation was achieved in the GaxIn1-xP material system via a strain-induced lateral-layer ordering process occurring spontaneously when (GaP)n/(InP)nshort-period superlattices are grown on (100)-oriented on-axis GaAs substrates. This results in a quasi-periodic modulation of the GaxIn1-xP composition along the [110] direction with a periodicity of 95 °A. Thin (≈200°A) layers of these laterally ordered regions imbedded between bulk lattice-matched Ga0.51In0.49P epilayers in the longitudinal direction form quantum wire arrays. The formation of multiple quantum wires is confirmed by cross-sectional transmission electron microscopy. The GaxIn1-xP multiple quantum wire heterostructure exhibits highly polarized photoluminescence spectra with peak intensity ratios of over 24 for the two orthogonal polarizations as a result of strain-induced lateral-layer ordering.