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

Published 2004-04-12, updated 2004-06-11Version 3

We have studied a 50/50\AA superlattice 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.