Removal of OH impurities from GeS2 by reactive atmosphere and its glass preparation

The transparency of the chalcogenide glasses depends upon the purity of the raw materials used for the glass preparation. Especially, the glasses used for optical fiber systems are generally prepared using high purity raw materials. In optical fiber glasses, the OH radicals are critical since they quench the fluorescence. In the present investigation, we have prepared germanium sulfide-based chalcogenide glasses. The sulfide usually contains significantly large amount of hydroxyl impurities which act as high energy phonons in the glass structure. These high energy phonons are known to quench fluorescence. Hence OH impurity removal is essential for optical fiber systems. Considering the criticality of OH impurity in optical fiber system, the efforts have been made to purify raw materials of germanium sulfide glasses. The present investigation focuses research on decreasing impurities content in the raw materials used for glass preparation. The GeS2, Ga2S3 powders were purified by reactive atmosphere of HCl and hydrogen. The glasses using these powders were melted and thermal and spectroscopic studies have been made.