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

The absorption and luminescent properties of α-ZnAl2S4:Co spinel type crystals grown by chemical transport reactions method are investigated. The spectra are assigned to the electronic transitions of Co2+ ions located in tetrahedral sites. It is shown, that the revealed four radiative spectral components are caused by the 2A(2G)→4T1(4F), 4T1(4P)→4T2(4F), 2E(2G)→ 4T2(4F) and 2E(2G)→4T1(4F) transitions.