The development of SiO2 resistant Cr-doped glass ceramics for high Cr4+ emission

The influence of SiO2 inter-diffusion into Cr-doped CaO–Al2O3 glass, Ca2GeO4, and Mg2SiO4 glass ceramics at high temperature is so severe that almost none of Cr4+ emission can remain. Although the Cr4+ emission can be recovered up to 13% from its pristine value after re-heat treatment in the initial composition of Mg2SiO4 glass ceramics, the new composition based upon SiO2 pre-deficiency technique proposed in this paper can retrieve up to about 4 times better, which indicates much less vulnerability to SiO2 incorporation. Further improvement is possible with finer composition optimization. The results indicate the potential of pre-deficiency technique for making high Cr4+ emission in silica-based optical fibers under the fact that the Cr4+ emission is seriously degraded upon SiO2 incorporation.