Optical study of high density two-dimensional electron gas in GaAs/Al 0.3Ga0.7As modulation-doped quantum wells
Journal
Journal of Applied Physics
Journal Volume
72
Journal Issue
2
Pages
647-650
Date Issued
1992
Author(s)
Abstract
We have investigated the optical properties of high density electron gas in GaAs/Al0.3Ga0.7As modulation doped quantum wells by using the photoluminescence measurements with the pumping photon energies above and below the band gap of the barrier and the resonant Raman scattering. We point out that the previous assignment of the transition between the second conduction subband and the ground-state heavy-hole subband in the photoluminescence spectra may be flawed. Thus, there is no large breakdown of the parity selection rule of the optical matrix element in quantum wells even if the carrier concentration is as high as 1012 cm−2. Our results are consistent with the theoretical investigation. We have also estimated the band gap shrinkages due to many-body interactions, which are comparable with the previous calculations.
Type
journal article