Transition metals are well known as optically active dopants in crystalline hosts because they fluoresce broadly in the near-IR; examples include Ti3+:sapphire (Al2O3) and Cr4+:forsterite (Mg2SiO4). Because transition element ions yield stronger optical activity with those of doped crystal. The glass-ceramic process can, in many cases, also allow the growth in glass of crystals which are difficult or impossible to obtain in single crystal form. Material properties and spectroscopic data are presented for transparent glass-ceramics based on transition element-doped forsterite, willemite, mixed Li-Zn-Mg- orthosilicates, and spinel crystals. The transition element ions include Cr4+ in tetrahedral coordination and Ni2+ in octahedral coordination. The optical property measurements of the transparent glass-ceramics, including absorbance, fluorescence, and fluorescence lifetimes, duplicate those reported in the literature for single crystal or powders. Cr4+- and Ni2+-doped glass-ceramics exhibit broad emission across the telecommunications wavelength range of 1100-1700 nm.
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