Mid-infrared emissions and energy transfer in Ge-Ga-S glasses doped with Dy3+

Abstract

Effect of sulfur level in Ge-Ga-S (Ge29.1Ga5S65.9, Ge25.8Ga5S69.2 and Ge32.4Ga5S62.6) glasses on the emission and nonradiative relaxation from the R-6(11/2) and H-6(13/2) levels in Dy3+ was investigated. Emission cross-sections and lifetimes of these two energy levels increased as the amount of sulfur decreased and the magnitude of the non-radiative relaxation decreased. We suggest that these changes in the emission properties show that glass deficient in sulfur, less than its stoichiometric GeS2-Ga2S3 composition, provides better potential as a laser source compared to those with an excess sulfur, (C) 1999 Elsevier Science B.V. All rights reserved.