Free and localized positively charged excitons in the emission spectrum of GaAs/AlGaAs quantum wells

The recombination emission spectra of an excitonic complex (A(0)X) localized on a neutral acceptor, which have previously been attributed to a positively charged exciton (X+), are investigated. Satellites arising around the main luminescence line as a result of recoil processes during recombination of the complex which leave the surviving hole in an excited state are observed and investigated. It is shown in a computational model based on the Luttinger Hamiltonian that the energy splittings between the main line and the satellites correspond to an in-barrier impurity center located a definite distance from the well. It is shown that as the magnetic field increases, a transition is observed from the singlet ground state of the complex to a multiplet state. (C) 1998 American Institute of Physics.