Photoluminescence of an AlAs/GaAs Superlattice Grown by MBE in the 0.7–0.8 µm Wavelength Region

AlAs/GaAs superlattices were grown by molecular beam epitaxy with a GaAs quantum well width L z of 20–160 Å. An X-ray diffraction technique is shown to be a practical and non-destructive method to measure L z with in an accuracy of 10%. A photoluminescence measurement showed a sharply peaked structure (Δ E≦ 50 meV) and indicated that the main carrier recombination process at room temperature is from the n=1 electron quantum level to the n=1 heavy hole level. Carrier concentration dependence of the photoluminescence energy differs from the usual Burstein-Moss shift. The highest emission energy obtained was 1.77 eV (7000 Å).