Synthesis and optical characterizations of Nd, Y: CaF2 transparent ceramics

Highly transparent Nd, Y co-doped calcium fluoride (Nd, Y: CaF2) ceramics with different Y3+ ions doped concentrations were fabricated by hot-pressed method using Nd, Y: CaF2 nanopowders synthesized by co-precipitation method. According to the XRD calculations and SEM observations, the average grain size of nanopowders was about 22 nm. From the SEM micrograph of the nanopowders, it clearly shows that the nanoparticles exhibit nearly spherical morphology and agglomerated slightly. For 2 mm thickness sample, the transmittance of the as-fabricated Nd, Y: CaF2 (1 at.% Nd and 2 at.% Y) ceramic at 1400 nm reached up to 87%. The microstructure, absorption spectra and emission spectra of the Nd, Y: CaF2 ceramics were measured and discussed. Compared with the Nd: CaF2 ceramic, the Nd, Y: CaF2 ceramics fluorescent intensity increased drastically with the increase of Y3+ ions doped concentration.