Luminescent properties of cobalt-doped α-ZnAl2S4 spinel type single crystals

The absorption and luminescent properties of α-ZnAl 2 S 4 :Co spinel type crystals grown by chemical transport reactions method are investigated. The spectra are assigned to the electronic transitions of Co 2+ ions located in tetrahedral sites. It is shown, that the revealed four radiative spectral components are caused by the 2 A( 2 G)→ 4 T 1 ( 4 F), 4 T 1 ( 4 P)→ 4 T 2 ( 4 F), 2 E( 2 G)→ 4 T 2 ( 4 F) and 2 E( 2 G)→ 4 T 1 ( 4 F) transitions.