Photoluminescence study of /spl alpha/-ZnAl/sub 2/S/sub 4/ single crystals

Photoluminescence (PL) spectra of ZnAl/sub 2/S/sub 4/ crystals with spinel structure were studied under the extrinsic excitation. The PL bands at 0.98 eV and 1.34 eV are suggested to be caused by native defects; while the bands at 1.61 eV and 2.0 eV are associated with the Cr and Mn impurities respectively. Mn/sup 2+/ intracentral transitions were investigated by the PL excitation spectroscopy.