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Measurement of miniband parameters of a doped superlattice by photoluminescence in high magnetic fields

R. F. Oliveira·A. B. Henriques·T. E. Lamas·A. A. Quivy·E. Abramof
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Abstract

We have studied a 50/50Åsuperlattice of GaAs/Al$_{0.21}$Ga$_{0.79}$As composition, modulation-doped with Si, to produce $n=1.4\times 10^{12}$ cm$^{-2}$ electrons per superlattice period. The modulation-doping was tailored to avoid the formation of Tamm states, and photoluminescence due to interband transitions from extended superlattice states was detected. By studying the effects of a quantizing magnetic field on the superlattice photoluminescence, the miniband energy width, the reduced effective mass of the electron-hole pair, and the band gap renormalization could be deduced.

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R. F. Oliveira, A. B. Henriques, T. E. Lamas, A. A. Quivy, E. Abramof. 2004-06-11. Measurement of miniband parameters of a doped superlattice by photoluminescence in high magnetic fields. https://doi.org/10.1088/0022-3727%2F37%2F21%2F002

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