IDENTIFICATION OF THE MULTICOMPONENT NATURE OF E-0 PHOTOREFLECTANCE SPECTRA FROM MODERATELY DOPED GAAS SUBSTRATES

The paper considers methods used to identify the multicomponent charac ter of photoreflectance (PR) spectra in the vicinity of the E-0 transi tion measured at room temperature from moderately doped GaAs substrate s. It is shown that that if an E-0 PR spectrum contains an excitonic c omponent, its presence can be established from both a mathematical and phase analysis, as well as from measurements performed at different l aser excitation densities. (C) 1997 American Institute of Physics.