Luminescence of GdF3:Pr:Yb and YF3:Pr:Yb Solid Solutions Synthesized by Crystallization from the Melt

• Published in: Journal of applied spectroscopy Vol. 86; no. 5; pp. 795 - 801
• Main Authors: Nizamutdinov, A. S., Kuznetsov, S. V., Konyushkin, V. A., Nakladov, A. N., Madirov, E. I., Voronov, V. V., Khadiev, A. R., Marisov, M. A., Semashko, V. V.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-11-2019; Springer Nature B.V
• Subjects: Analytical Chemistry; Atomic/Molecular Structure and Spectra; Cross relaxation; Crystallization; Energy transfer; Luminescence; Photosensitivity; Physics; Physics and Astronomy; Solid solutions; Synthesis; rare-earth ions; down-conversion luminescence; nonradiative energy transfer; fluorides
• ISSN: 0021-9037; 1573-8647
• DOI: 10.1007/s10812-019-00895-1

Spectral and luminescence characteristics of GdF
3
:Pr:Yb and YF
3
:Pr:Yb solid solutions synthesized by crystallization from the melt were investigated. Down-conversion luminescence of Yb
3+
in the region of
2
F
5/2
→
2
F
7/2
transitions with 445-nm excitation was studied. The energy-transfer coefficient from Pr
3+
to Yb
3+
was <80% for concentration ratios Pr/Yb 0.5/10.0 and 1.0/10.0 for GdF
3
and 0.5/10.0 for YF
3
. The absolute values of Pr
3+
and Yb
3+
luminescence quantum yields in the region of the greatest crystalline-silicon photosensitivity were low because of highly efficient nonradiative energy transfer. The quantum yield was <1% for Yb
3+
intrinsic luminescence and <4% for total luminescence in the range 800–1050 nm (for concentration ratio Pr/Yb = 0.5/1.0 in GdF
3
matrix). The low quantum yield was a consequence of the complex energy-exchange pattern between Yb
3+
and Pr
3+
ions, which was largely influenced by the proximity of
1
G
4
and
2
F
5/2
energy states of Pr
3+
and Yb
3+
, respectively, in these matrices. This opened an additional pathway for nonradiative decay of Yb
3+
excited states and enabled cross-relaxation between
3
P
0
→
1
G
4
transitions of Pr
3+
and
2
F
5/2
→
2
F
7/2
transitions of Yb
3+
that increased the lifetime of the Pr
3+ 3
P
0
state.