High photoluminescence in erbium-doped chalcogenide thin films

The spectral properties of the chalcogenide glasses As2S3 and As24S38Se38-doped with Er3+ are presented and discussed, Thin films were formed by thermal evaporation and the erbium doping was obtained by subsequent ion implantation. Strong Er3+ emission at 1.54 mu m has been observed. The high refractive index of these chalcogenide glasses lead to Er3+ emission cross-sections (15 x 10(-21) cm(2)) which are two times higher than for doped silica glass. The lifetime of the Er3+ metastable I-4(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 Er3+ I-4(11/2) pump level, which have been measured to be of the ol-der of 0.25 ms. These spectral properties make this glass a good candidate for applications in the field of integrated optics. (C) 2000 Elsevier Science B.V. All rights reserved.