Study of the environment of Er in ZnSe using extended x-ray absorption fine structure and optical spectroscopy

Extended x-ray absorption fine-structure measurements have been performed o n ZnSe crystals doped with Er by an addition of ErF3 during growth. The res ults show that Er exists in these samples in an orthorhombic configuration with nine nearest F neighbours similar to that in orthorhombic ErF3. The en ergy level splittings observed in optical absorption and photoluminescence investigations in the region of the 4I(15/2) <----> I-4(13/2) transitions a t 1.54 mum are fully consistent with the orthorhombic. symmetry of the Er c entre.