Ir. Martin et al., Infrared, blue and ultraviolet upconversion emissions in Yb3+-Tm3+-doped fluoroindate glasses, SPECT ACT A, 55(5), 1999, pp. 941-945
Citations number
15
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences
Journal title
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
Intense ultraviolet (362.5 nm), blue (479 nm) and IR (800 nm) upconversion
emissions were obtained in fluoroindate glasses co-doped with Yb3+ and Tm3 ions pumped at 975 nm. The dependence of these upconversion emissions on e
xcitation intensity has been studied and it is concluded that emissions com
e from Tm3+ ions excited by successive energy transfers from Yb3+ ions. The
temporal evolution of the 800 nm upconversion emission obtained under flas
h excitation at 975 nm cannot be described using the energy migration model
. This indicates that at this concentration of Yb3+, the rapid migration re
gime among these ions has not been reached. A model is proposed in order to
explain the temporal evolution of this emission, taking into account back-
transfer processes from Tm3+ to Yb3+ ions. (C) 1999 Elsevier Science B.V. A
ll rights reserved.