Enhancing fluorescence emission properties of Dy3+ doped in chalcogenide glass via very small compositional modifications

It has been experimentally confirmed that the addition of very small amount, tantamount to similar to 1 mol%, of the group III elements (Ga or In) in combination with alkali halides (CsBr or RbBr) into chalcogenide Ge-As-S glass significantly improves the emission properties of Dy3+ dopant. Preferential location of Br in the first coordination shell of Dy3+, which occurs spontaneously during the vitrification process, is proposed to make Dy3+ experience different crystal fields, reduced phonon energy and modified local refractive index. This restructuring effect as a result of such minute compositional adjustments thus enhances the optical properties of rare earth elements embedded in chalcogenide glasses, while keeping their thermal properties unaltered. (c) 2009 Elsevier B.V. All rights reserved.