Spectroscopy of be acceptor ground state in GaAs/AlGaAs heterostructure

Photoluminescence measurements were carried out on Be delta-doped GaAs/Al0.33Ga0.67As heterostructure at 1.6 K in magnetic fields (B) up to 4 T. Luminescence originating from recombination of a two-dimensional electron gas and photoexcited holes localized on Be acceptors was analyzed. The degree of circular polarization (gamma C) of the luminescence from fully occupied Landau levels was determined as a function of B and the two-dimensional electron gas concentration, n(s). At B constant, gamma C decreased with the increase in n(s),. The intensity of the optical transition considered was calculated with taking into account s- and d-like parts of the acceptor envelope function. It is shown that the presence of the d-like part explains the observed gamma C(n(s)) dependence quantitatively. This shows that polarization spectroscopy on acceptor delta-doped heterostructures enables one to test experimentally the contribution of the L > 0 component of the envelope in a shallow acceptor description.