Effect of Yb3+ concentration on microstructure and optical properties of Yb: SrF2 transparent ceramics

Ytterbium-doped strontium fluoride (Yb: SrF 2 ) nanopowders with different amounts of Yb 3+ were synthesized by a co-precipitation method. XRD and FE-SEM measurements were used to characterize the phase composition and morphologies of these nanopowders. The Yb: SrF 2 nanopowders doped with 1–5 at.% Yb 3+ showed the same phase as pure SrF 2 , with a mean particle size of 20 nm. Transparent Yb: SrF 2 ceramics were fabricated by hot-pressing the nanopowders, and the transmittance of 1 at.% Yb: SrF 2 with a thickness of 2 mm was 85% at 1200 nm. The absorption spectra , luminescence spectra, and luminescence decays of the ceramics were also obtained. As the Yb 3+ doping amount increased, the absorption and emission intensities also increased, indicating the absence of a concentration quenching effect in the Yb: SrF 2 ceramics. However, the decay lifetimes decreased with increasing Yb 3+ content, and 1–5% Yb: SrF 2 transparent ceramics had decay lifetimes of 4.58, 3.48, 3.22, and 3.19 ms, respectively.