High photoluminescence in erbium-doped chalcogenide thin films

Abstract

The spectral properties of the chalcogenide glasses As 2S 3 and As 24S 38Se 38-doped with Er 3+ are presented and discussed. Thin films were formed by thermal evaporation and the erbium doping was obtained by subsequent ion implantation. Strong Er 3+ emission at 1.54 μm has been observed. The high refractive index of these chalcogenide glasses lead to Er 3+ emission cross-sections (15×10 −21 cm 2) which are two times higher than for doped silica glass. The lifetime of the Er 3+ metastable 4I 13/2 energy level was measured to be 2.3 ms. This short lifetime is consistent with the high emission cross-section. Furthermore, the very low phonon energies of chalcogenide glasses lead to relatively long lifetimes of the Er 3+ 4I 11/2 pump level, which have been measured to be of the order of 0.25 ms. These spectral properties make this glass a good candidate for applications in the field of integrated optics.