Abstract

Pr³⁺-doped Ge-S-I glasses have been synthesized. Their optical and thermal properties were studied in regard to the material requirements for 1.31 μm optical fiber amplifier. The glass composition Ge₃₅ S_56.5 I_8.5 was selected as an optimum host for this application.. The measured ¹G₄ lifetime (368 μs) and quantum efficiency (82 %) in bulk samples of this composition are outstanding compared to these parameters measured in other candidates capable of fiberization. This glass host allows solubility of Pr³⁺ ions up to 2000 ppm/wt, which exceeds several times the practical level of Pr³⁺ doping limited by concentration quenching. Homogeneous glass rods with typical lengths more than 6 cm and Pr³⁺ concentrations 500 ppm/wt of the composition selected for drawing were produced. Fibers with diameter 200 μm and polymer coating were fabricated in more than 15 meters lengths. Fiber losses of 3 dB/m at 1.31 μm were measured in best samples.

© 1997 Optical Society of America