High resolution spectroscopy of defect bound excitons and acceptors in GaAs grown by molecular beam epitaxy.

New results on the groups of luminescence lines from defect bound excitons and defect-complex acceptors in GaAs grown by molecular beam epitaxy are reported. Both series of spectra are found to be polarized, thus establishing a strong link between them. Resonantly excited two-hole satellites of the defect bound excitons are observed, supporting their identification as arising from exciton recombination at axial acceptor centries. Calculation of acceptor binding energies from the two-hole satellite displacements leads to reasonable agreement with those found from the electron to shallower defect-complex acceptor bands, providing a further clear connection between the two sets of bands.