Relationship between microstructure and the achieving of the single-band red upconversion fluorescence of Er3+/Yb3+ codoped crystallites

Abstract

Abstract The as-cast and the heat-treated samples with the primary mole composition of (59.4 − x )ZnF 2 –40PbF 2 –0.1B 2 O 3 – x Yb 2 O 3 –0.5Er 2 O 3 ( x = 2, 4, 7, 10, 13) were synthesized. In the as-cast and the heat-treated samples with 13 mol% Yb 2 O 3 , the multi-band and the single red band upconversion (UC) lights were observed, respectively, under the excitation of a laser diode (LD) with excitation wavelength of 980 nm. For this interesting phenomenon, microstructure analysis revealed that the crystal phases and the distribution of Er 3+ ion has been changed by the heat-treatment and the mole ratio of Yb 3+ to Er 3+ ion in the neighbor environment of Er 3+ ion is increased from 0.74 to 16.96 which brought about the populating behavior variation of 4 F 7/2 and 4 F 9/2 levels of Er 3+ ions, to which the achieving of the dazzlingly single-narrow-band red light was ascribed.