Silva H.M.,Brazilian Nuclear Energy Research Institute (IPEN) |
Courrol L.C.,Federal University of Sao Paulo |
Gomes L.,Brazilian Nuclear Energy Research Institute (IPEN) |
Bertram R.,Institute For Kristallzuchtung Ikz |
And 2 more authors.
Journal of Physics: Conference Series | Year: 2010
Energy transfer processes that generate thulium blue and ultraviolet emissions by upconversion were studied in KY3F10:Tm (KY3F:Tm), using Nd3+ and Yb3+ as sensitizers of Tm 3+. The upconversion mechanisms were determined by exciting into the Nd and Tm absorption bands with a diode laser at 797nm. It was observed that the intensity of the Tm3+ blue and ultraviolet emissions in 484, 453, 366 and 350 nm were very dependent of the Yb3+ concentration in the samples, confirming that the main energy transfer processes involve Nd 3+ and Yb3+ ions. KY3F10:Nd (1.3 mol%):Tm (0.5 mol%) crystals codoped with 5, 10, 20 and 30 mol% Yb were prepared by slow cooling from the melt, to establish the optimal Yb concentration that maximizes the Nd3+Yb3+Tm3+ energy transfer. © 2010 IOP Publishing Ltd.