Abstract
Photoelectron spin polarizations of 50 and 17% have been obtained with the chalcopyrite‐structure semiconductors ZnSiAs2 and ZnGeAs2, respectively, by irradiation with circularly polarized light. A comparison is made with the results obtained from GaAs, which has a zinc‐blende structure. An analysis of the chalcopyrite electron‐level structure shows that polarizations up to 100% can be expected for suitably chosen materials.