Mechanism of the enhancement of mid-infrared emission from GeS2-Ga2S3 chalcogenide glass-ceramics doped with Tm3+

We report the fabrication and characterization of 80GeS(2)center dot 20Ga(2)S(3):0.5Tm(2)S(3) chalcogenide glass-ceramics. A careful thermal process has led to the formation of similar to 50 nm Ga2S3 nanocrystals. By monitoring the H-3(5)-> F-3(4) Tm3+ transition, an almost fivefold increase of in the intensity and similar to 76 mu s prolongation in the lifetime of mid-infrared fluorescence at 3.8 mu m have been observed after crystallization. Element mapping evidenced that enhancement in the mid-infrared emission intensity was related to the formation of Ge-rich region in the glass-ceramics, consistent with spectroscopic results from glasses with different levels of GeS2 content and beta-GeS2 precipitation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4727900]