Hydrogenation and annealing effects on electronic subbands in modulation-doped Al0.25Ga0.75As/In0.18Ga0.82As/GaAs strained single quantum wells

Photoluminescence (PL) measurements have been carried out to investigate the hydrogenation and annealing effects on the excitonic transitions in modulation-doped Al0.25Ga0.75As/In0.18Ga0.82As/GaAs strained quantum wells. After hydrogenation, the PL spectra showed that the excitonic transition energy from the ground electronic subband to the ground heavy-hole subband (E-0 - HH1) shifted to a higher energy. When the hydrogenated Al0.25Ga0.75As/In0.18Ga0.82As/GaAs quantum wells was annealed, the (E-0 - HH1) peak shifted to a lower energy. The electronic subband energies, the energy wave functions, and the Fermi energies in the as-grown modulation-doped Al0.25Ga0.75As/In0.18Ga0.82As/GaAs quantum wells were calculated by a self-consistent method taking into account exchange-correlation effects together with the strain and nonparabolicity effects. These results indicate that the energy levels of the electronic subbands in the In0.18Ga0.82As quantum well are dramatically affected by the hydrogenation and the annealing and that the shifts of their energy levels due to the hydrogenation and the annealing can help improve understanding of the promising applications of modulation-doped Al0.25Ga0.75As/In0.18Ga0.82As/GaAs strained quantum wells in optoelectronic devices. (C) 1999 Elsevier Science Ltd. All rights reserved.