On the near-infrared luminescence from TeO2 containing borate glasses

The effects of melting temperature and glass composition on the Near-infrared (NIR) luminescent characteristics of Te-containing borate glasses are investigated and compared with previous works. Three absorption bands are detected at around similar to 370 nm, similar to 430 nm and similar to 530 nm, however, the absorption band at around -600 nm could not be detected in all borate glasses. And no NIR luminescence was observed under the excitation of a 974 nm laser diode. The NIR luminescence was observed in Te-green and Te-purple glasses, which showed the absorption band at around similar to 600 nm. This absorption band was ascribed to (2)Pi g -> (2)Pi u transition of Te-2(-). Consequently, it is suggested that the origin of NIR luminescence of Te-containing green and purple glass is likely to be caused by Te2- center. (Not to sure of the meaning of this sentence...) (C) 2008 The Ceramic Society of Japan. All rights reserved.