Magneto-optical spectroscopy of modulation-doped GaAs AlGaAs asymmetric coupled double quantum wells

We have presented the magneto-optical studies of modulation-doped GaAs/AlGaAs asymmetric coupled double quantum wells. The transition energies of two asymmetric quantum wells are in good agreement with those obtained from a self-consistent calculation. The effective mass of the first subband electron is found to be larger than that of the second subband electron. This means that, by virtue of the band bending effects, the first electron subband originates from a narrow well and the second from a wide well. The magnetic-field dependence of Landau-level transitions between the second electron subband and the first heavy-hole subband shows an enhancement of an excitonic emission near the Fermi edge. (C) 1999 Elsevier Science Ltd. All rights reserved.