Photoluminescence in Er-doped Ge-Ga-Se glasses

The optical properties of Er-doped Ge-Ga-Se glasses prepared by melt quenching techniques have been investigated. They were doped using Er2S3 and were stable as shown by temperature modulated differential scanning calorimetry. The influence of doping with Er on the photo luminescence, optical absorption and structural properties of Ge-Ga-Se glasses has been investigated and the strong correlation between the Er and Ga concentrations (C-Er and C-Ga) and the properties of these glasses has been revealed. High C-Ga/C-Er > 10 ensures the homogeneous distribution of Er in host volume. Low C-Ga/C-Er < 3 leads to formation of chemical clusters found in the form of Er enriched crystalline inclusions. Intermediate region 3 < C-Ga/C-Er < 10 is characterized by the formation of "physical clusters" or "clusters of interaction" where the Er ions are not connected chemically but the energy can effectively migrate form one ion to another. (c) 2004 Elsevier B.V. All rights reserved.