Growth and optical properties of Pr,Yb-codoped KY3F10 fluoride single crystals for up-conversion visible luminescence

We investigate different ways to realize laser emission from (Pr3+) 3PJ=0,1,2 levels by pump sources other than the common argon and excimer-dye laser. The use of infrared (IR) laser diodes in combination with intra- and inter-ionic energy transfer processes (up-conversion) could be an efficient solution towards laser oscillation. Pr3+,Yb3+-codoped KY3F10 (Pr, Yb:KYF) single crystals were successfully grown by the micro-pulling-down (μ-PD) method. The crystals were transparent with a slightly greenish color, 2.0–2.5 mm in diameter, 20–30 mm in length and free from visible inclusions and cracks. Effective segregation coefficients of Pr and Yb in KYF were studied by means of absorption and chemical analysis. Strong visible emission via selective IR pumping with λ=975 nm and up-conversion excitation were obtained in Pr, Yb:KYF at room temperature (RT). Luminescence measurements have been carried out and the decay kinetics of the Pr3+ visible emissions was investigated by room temperature time-resolved spectra.