Özet:

Solid state synthesis of Perovskite-like calcium stannate structure activated with three rare-Earth metal ions Yb3+,Er3+,Но3+ has been studied. The formation of the CaSnO3 : Yb3+,Er3+,Но3+ luminescent structure requires the following synthesis conditions: anneal temperature 1250 °C and duration at least 18 h. The luminescent properties of the specimens have been studied under 960 nm semiconductor diode laser excitation. The luminescence spectra contain bands in the visible and IR spectral regions. Yb3+ ions have been shown to act predominantly as sensibilizers capable of transferring part of absorbed energy to Er3+ and Но3+ ions thus intensifying their respective luminescence peaks. Er3+ ions also transfer part of absorbed energy to Но3+ ions leading to an increase in the intensity of the 1194 and 1950 nm IR luminescence bands. A schematic of possible energy transitions in the CaSnO3 : Yb3+,Er3+,Но3+ system under 960 nm laser excitation has been suggested. The energy transfer mechanism between Yb3+,Er3+ and Но3+ions has been described in detail. The luminescence intensity of the luminophore has been studied at 994, 1194, 1550 and 1950 nm as a function of Но3+ion concentration. The peak intensity of the 1194 and 1950 nm bands is the highest at a Но3+ion concentration of 0.007 at.fr. It has been suggested to use the CaSnO3 : Yb3+,Er3+,Но3+ luminescent structure for radiation sources capable of converting 960 nm IR radiation to ~2000 nm IR radiation.

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