Effects of heavy p doping on the polarized emission spectra and low-temperature luminescence spectra of GaAs/GaAsP strained-layer structures

The optical orientation of electron spins in heavily doped, strained GaAs/G aAsP layers with a deformation-split valence band is studied experimentally . The observed polarized luminescence spectra and polarized photoemission ( electron emission) spectra are shown to be described well by a model which allows for smearing of the edges of the bands by the fluctuation potential due to impurities, degeneracy of the carriers at low temperatures, and indi rect electron-phonon optical transitions. The dominant mechanism of electro n spin relaxation in strained layers is found to be the Bir-Aronov-Pikus me chanism. The parameters of the fluctuation potential and the parameters gov erning carrier spin relaxation are determined. (C) 1999 American Institute of Physics. [S1063-7826(99)00711-5].