Photoluminescence study of acceptor states in n-type, modulation doped GaAs/AlGaAs multiple quantum wells

In many n-type modulation-doped GaAs/AlGaAs multiple quantum well (MQW) heterostructures, a replica of the band-to-band luminescence spectrum appears at a lower energy (ΔE = 25 meV). This new feature is attributed to electronic transitions from the conduction band to residual carbon acceptors. In a magnetic field this "Acceptor Replica" breaks into two sets of lines associated with transitions from the conduction band Landau levels to the ground state and to an excited state of the acceptor. The field dependence of these transitions is studied and the binding energies of the acceptor states are determined.