Recent photoluminescence research on chalcogenide glasses for photonics applications

The optical properties of GeGaSe glasses doped with Er by the addition of Er2S3 have been investigated. Optically uniform glasses have been prepared using stoichiometric compositions with 9–12 at.% Ga and doped with 0.5–2 at.% Er. The radiative lifetime of the 4I13/2 → 4I15/2 transition has been estimated to be equal to 1.78 ms using the Judd–Ofelt analysis. The photoluminescence lifetime distribution has been investigated in optimized glasses using Quadrature Frequency-Resolved Spectroscopy at room and liquid helium temperatures and at different emission wavelengths. All lifetime distributions were found to be sharp peaks centered at ∼2 ms. A radiation diffusion model has been used to understand the discrepancy between measured photoluminescence spectra and those predicted by the McCumber theory. The model predicts a radiative lifetime of the 4I13/2 → 4I15/2 transition to be around 1.72 ms and a much longer non-radiative lifetime. These results assume quasi-uniform distribution of Er3+ ions with negligible concentration-self-quenching and negligible rate of non-radiative relaxation from 4I13/2 to 4I15/2.