Biaxial and uniaxial stress in gallium arsenide on silicon: A linear polarized photoluminescence study

Abstract
We have observed anisotropic behavior of the polarization of low-temperature photoluminescence from thick gallium arsenide grown on silicon substrates. The identification of the observed transitions was obtained from analysis of the selection rules, the temperature dependence of the feature intensities, and the transition energies. We find that the low-temperature doublet peaks are due to the emissions from two regions of material experiencing two different kinds of stress, one being biaxial and the other uniaxial. The anisotropy is due to the preferential direction created by parallel microcracks.