Optical spectroscopy and visible stimulated emission of Dy3+ ions in monoclinic α-KY(WO4)2 and α-KGd(WO4)2 crystals -: art. no. 125108

The complex crystallographic, spectroscopic, and laser properties of Dy3+ ions in alpha-KY(WO4)(2) and alpha-KGd(WO4)(2) single crystals are investigated. Individual Stark levels for many of the L-2S+1(J) manifolds of Dy3+ (4f(9)) ions in these monoclinic tungstates are obtained from luminescence and absorption spectra up to approximate to28 000 cm(-1) at approximate to15 K. A crystal-field splitting analysis for the majority of these manifolds is performed. The rms deviation between 73 experimental and calculated Dy3+ Stark levels for both crystals was approximate to10 cm(-1). Theoretical calculations of intermanifold intensity parameters are carried out by methods using the Judd-Ofelt approach with regard to interconfiguration interaction. All luminescence channels originating from levels of the metstable F-4(3)(9/2) state are compared with measured data. Pulsed stimulated emission in the visible range at the wavelengths of two lasing channels F-4(3)(9/2)-->H-6(13/2) and F-4(3)(9/2)-->H-6(11/2) of Dy3+ ions are excited and identified. On the basis of observed spectroscopic data we determine the peak cross section for all observed induced transitions as well. We conclude that Dy3+-doped monoclinic tungstates alpha-KGd(WO4)(2) and alpha-KY(WO4)(2) are very attractive crystalline materials for generating visible laser light.