Influence of structure defects on the radiative recombination in gallium arsenide crystals

A reduction in the number of structure defects by altering the conditions during growth of GaAs crystals from the melt increased hundredfold the quantum efficiency of the radiative recombination and improved considerably the parameters of electron-beam-excited lasers. The presence of structure defects was detected by precision weighing of crystals. The dependence of the photoluminescence spectra on the density of crystals suggested that the luminescence band at ~1.35 eV was due to arsenic vacancies.