Near infrared and blue cooperative emissions in Yb3+-doped GeO2-PbO glasses

In previous years there has been great interest in new materials for photonic devices operating at infrared (IR) and visible (VIS) regions. We report here near infrared and blue cooperative luminescence properties for Yb3+-doped GeO2-PbO glasses. Luminescence and lifetime measurements in the VIS and near-IR regions were performed to investigate the spectroscopic characteristics of the glasses. Intense emissions around 507 and 1010 nm were observed using 980 and 808 nm excitation, respectively. The VIS lifetimes (similar to 0.4 ms) are about half of their respective near infrared ones (similar to 0.8 ms), as expected for materials in which the VIS emission is caused by the cooperative effect. Regarding the IR emission, the glasses exhibited a high absorption cross-section (1.2 x 10(-20) cm(2)) at 978 nm and an emission cross-section of 0.6 x 10(-20) cm(2), at 1010 nm, with a minimum pump intensity of 2.8 kW/cm(2). These results suggest this glass composition as a potential material to be used in devices operating in the VIS and IR spectral range, such as 3-D displays and infrared lasers. (c) 2005 Elsevier B.V. All rights reserved.