Conduction electrons in acceptor-doped GaAs/GaAlAs heterostructures: a   review
  We review magneto-optical and magneto-transport effects in GaAs/GaAlAs heterostructures doped in GaAlAs barriers with donors, providing two-dimensional electron gas in GaAs quantum wells, and additionally doped with smaller amounts of acceptors (mostly Be atoms) in the vicinity of 2DEG. One may also deal with residual acceptors (mostly C atoms). The behavior of such systems in the presence of a magnetic field differs appreciably from those doped in the vicinity of 2DEG with donors. 
Wlodek Zawadzki, Andre Raymond, and Maciej Kubisa
cond-mat.mtrl-sci