Upconversion luminescence of Er3+ / Yb3+ -codoped germanium - gallium - sulfide glass-ceramics

In this work, Er³⁺ doped and Er³⁺/Yb³⁺ co-doped glass ceramics in the GeS₂ - Ga₂S₃ - CsCl system were prepared. The photoluminescence efficiency of the material depends largely on the local environment of the rare earth ions. It is particularly strong if the rare earth ions are situated inside crystals. By applying appropriate heat treatments to some glass compositions, it is possible to generate crystalline phases embedded in a glassy matrix.