EXCITONS BOUND AT INTERACTING ACCEPTORS IN ALXGA1-XAS GAAS QUANTUM-WELLS/

We have studied the effect of increasing acceptor concentration (betwe en 10(16) and 10(18) cm(-3)) on bound excitons (BE's) using steady-sta te photoluminescence (PL) and PL excitation spectroscopy. With increas ing doping concentration, an additional peak is observed on the low-en ergy side of the principal neutral acceptor BE. This peak is associate d with BE's formed by excitons bound at interacting acceptors, similar to the undulation spectra observed at high acceptor doping in differe nt bulk materials, such as ZnTe, InP, acid GaP. The exciton-impurity c omplexes are formed as the avenge distance between the acceptor impuri ties decreases with increasing doping concentration. The dependence of the optical properties of this exciton on temperature. excitation int ensity, and magnetic field is presented.