There has recently been a great deal of interest in searching for new materials for application as hosts in infrared-tovisible
light upconverters or optical amplifiers based upon rare-earth doped systems. Some of their many applications
include: color displays, high density optical recording, biomedical diagnostics, infrared laser viewers and indicators,
fiber lasers and amplifiers. Fluorosilicate based sol gel glass ceramics have recently emerged as auspicious candidates
for such photonic devices applications. These glasses are advantageous because they present low temperature of
preparation, better mechanical strength, chemical durability, and thermal stability than fluoride-based glasses. The
present work involves the investigation of optical transitions and upconversion fluorescence spectroscopy of trivalent
lanthanide ions Er3+ codoped with Yb3+ in β-PbF2 nanocrystals dispersed in silica glassy matrix, excited with nearinfrared
diode lasers. The dependence of the upconversion luminescence upon diode laser power, and the upconversion
excitation mechanisms involved are also investigated.
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