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

Abstract

Rare earth doped chalcogenide-halide glasses have been considered as potential candidates for the development of new laser sources, thanks to their low phonon energies and their transparency that extends from visible up to middle-far infrared. Furthermore, rare earth doped materials capable of converting infrared radiation into visible light through upconversion luminescence have gained special interest since they appear as a efficient solution to obtain visible lasers by pumping with commercial infrared laser diodes [1,2]. Chalcogenide glasses based on sulfides are an excellent candidate for this application since they have a wide visible and infrared transparency, in addition to their low phonon energies. In this work, Er ³⁺ doped and Er ³⁺ /Yb ³⁺ co-doped glass ceramics in the GeS 2 - Ga 2 S 3 - CsCl system were prepared. The 70(GeS 2 ) - 20(Ga 2 S 3 ) - 10(CsCl) glass composition was selected and appropriate heat treatments were applied to obtain transparent glass ceramics with various degrees of ceramization [3].