Upconversion luminescence of Ho3+ sensitized by Yb3+ in transparent glass ceramic embedding BaYF5 nanocrystals

Abstract Transparent SiO 2 –Al 2 O 3 –BaCO 3 –YF 3 –BaF 2 glass ceramics co-doped with Yb 3+ /Ho 3+ ions were prepared by melt quenching and subsequent heating. X-ray diffraction and transmission electron microscopy observation revealed that BaYF 5 nanocrystals incorporated with Yb 3+ and Ho 3+ were precipitated homogeneously among the oxide glass matrix. Three upconversion emission bands centered at 483 nm, 545 nm and 645 nm, corresponding to the 5 F 3 → 5 I 8 , 5 S 2 , 5 F 4 → 5 I 8 and 5 F 5 → 5 I 8 transitions of Ho 3+ respectively, were detected under 976 nm excitation, ascribing to the efficient energy transfer from Yb 3+ to Ho 3+ . The red emission is prevailing in the precursor glass, while the green one turns to be dominant in the glass ceramic.