PHOTOLUMINESCENCE LINE-SHAPE ASSOCIATED WITH E-A(0) ACCEPTOR-RELATED RECOMBINATION IN GAAS-(GA,AL)AS QUANTUM-WELLS UNDER APPLIED ELECTRIC-FIELD

A systematic study of the e-A0 acceptor-related photoluminescence spec tra in GaAs-(Ga,Al)As quantum wells under applied electric field is pr esented. The approach we adopt is based on the effective-mass approxim ation and a variational procedure for determining the acceptor energy and envelope wave function. The impurity-related photoluminescence lin e shape depends on the strength of the longitudinally applied electric field, the temperature, the quasi-Fermi energy of the conduction-subb and electron gas, and on the acceptor distribution along the quantum w ell. We find that the spectrum line shapes are essentially characteriz ed by the presence of three features, namely, one peaked structure ass ociated with transitions involving acceptors with binding energies at the top of the impurity band and two van Hove-like structures related to acceptors at the two edges of the quantum well.