In this work we report on visible upconversion emission in Er³⁺- and Ho³⁺-doped PbGeO₃-PbF₂-CdF₂-based transparent glass ceramics under 980 nm infrared excitation. In erbium-doped vitroceramic samples, blue(410 nm), green(530, and 550 nm) and red(660 nm) emission signals were generated, which were identified as due to the ²H_9/2, ²H_11/2, ⁴S_3/2, and ⁴F_9/2 transitions to the ⁴I_15/2 ground-state, respectively. Intense red(650 nm) upconversion emission corresponding to the ⁵F₅-⁵I₈ transition and very small blue(490 nm) and green(540 nm) signals assigned to the ⁵F_2,3-⁵I₈ and ⁴S₂,⁵F₄-⁵I₈ transitions, respectively, were observed in the holmium-doped samples. The 540 nm is the dominant upconversion signal in Ho³⁺-doped vitroceramics under 850 nm excitation. The dependence of the upconversion processes upon pump power and doping concentration are also investigated, and the main routes for the upconversion excitation processes are also identified. The comparison of the upconversion process in transparent glass ceramics and the precursor glass was also examined and the results revealed that the former present higher upconversion efficiencies.

Date Published: 14 June 2004
PDF: 8 pages
Proc. SPIE 5350, Optical Components and Materials, (14 June 2004); doi: 10.1117/12.523360

Published in SPIE Proceedings Vol. 5350:
Optical Components and Materials
Michel J. F. Digonnet; Shibin Jiang, Editor(s)