A study of high-energy photon emission (hν-eVkT) from various GaAs diodes is reported and the results analyzed. We find that this emission is produced by most diffused diodes except those doped with Sn and Ge. It is not observed in solution-grown diodes, no matter what the doping. It is always accompanied by a large amount of excess (nonradiative) current and can be explained in terms of the Auger recombination of carriers at defects with subsequent diffusion of the excited electrons to the p side of the junction. © 1966 The American Physical Society.