OPTICAL CHARACTERIZATION OF PR3+ AND DY3+ DOPED CHALCOGENIDE GLASSES

The optical properties of several sulfur-based glasses doped with Pr3 and Dy3+ have been measured, with emphasis on the 1.3 mu m emission q uantum efficiency. Glass hosts prepared using conventional methods inc lude As2S3+ As2S3 with 1.7 mol% I-2, Ge30As10S60, Ge25Ga5S70, and Ge35 S56.5I8.5 for Pr3+, and all but the As2S3 based compositions for Dy3+. Data obtained from optical absorption and fluorescence spectra and fl uorescence lifetime measurements were used for theoretical predictions of quantum efficiency. These theoretical efficiencies were compared t o absolute efficiency measurements using either an integrating sphere based system or a self-calibration technique (Pr3+ only, no As2S3-base d glasses). The latter method produced erroneous values for glasses ha ving electronic absorption edges beyond 500 nm, possibly due to a host sensitization phenomenon. A 100 ppm Pr2S3 doped GeGaS glass was the m ost efficient at 1.3 mu m, measuring 93% via the integrating sphere te chnique. The measured efficiencies for Dy3+ doped glasses at 1.3 mu m, the first reported to our knowledge, were less than those theoretical ly predicted. The most efficient Dy3+ doped sample, a 0.1 wt% Dy2S3 do ped GeSI glass, was measured to be 6%.