Studies of free-to-bound acceptor photoluminescence in an applied magnetic field for undoped GaAs grown by metalorganic vapor-phase epitaxy and molecular-beam epitaxy

Photoluminescence in an applied magnetic field is shown to be useful for the identification of trace acceptor impurities in GaAs. For an epitaxial layer grown by metalorganic vapor-phase epitaxy (MOVPE), a trace concentration of zinc acceptors was detected in a sample where the zinc transitions were obscured in zero magnetic field. In material grown by molecular-beam epitaxy (MBE), the 1.47-eV transition was identified as a conduction-band-to-deep-acceptor process. Also identified was a shallow impurity, magnesium or beryllium, not detected in zero field. Resolved Landau level transitions and the magnetic splitting of conduction-band-to-acceptor transitions were observed in both MOVPE and MBE material.