%0 Journal Article
%T Optical spectroscopy and local structure of the Nd3+ luminescence centres in glasses of the CaO每Ga2O3每GeO2 system
%A Bohdan Padlyak
%A Witold Ryba-Romanowski
%A Radoslaw Lisiecki
%J Optica Applicata
%D 2008
%I 
%X Optical absorption and luminescence spectra as well as luminescence kinetics of the Nd3+ centres in glasses with Ca3Ga2Ge3O12:Nd composition, containing 0.2 and 1.0 wt% of the Nd2O3 were presented and analysed. The oscillator strengths and phenomenological intensity parameters 次t (次2, 次4, and 次6) were obtained using standard Judd每Ofelt theory. Calculated 次t parameters, radiative transitions rates, branching ratios and radiative lifetime for Nd3+ centres in the glass with Ca3Ga2Ge3O12 composition were analysed and compared with corresponding Nd3+ parameters in their crystalline analogue with garnet structure. Experimental lifetimes are compared with those calculated, and quantum efficiency of Nd3+ centres from 4F3/2 emitting level in the glass with Ca3Ga2Ge3O12 composition is estimated. Incorporation peculiarities and local structure of Nd3+ luminescence centres in the glass with Ca3Ga2Ge3O12 composition and corresponding Ca3Ga2Ge3O12:Nd3+ garnet laser crystals are considered. On the basis of extended X-ray absorption fine structure (EXAFS) spectra (L3-edge) of rare-earth elements analysis it has been shown that Nd3+ luminescence centres in the CaO每Ga2O3每GeO2 glass network occupy structural sites with the coordination number to oxygen N = 6.
%K germanate glasses
%K Nd3+ centre
%K optical absorption
%K luminescence
%K decay kinetics
%K extended X-ray absorption fine structure (EXAFS)
%K local structure
%U http://www.if.pwr.wroc.pl/~optappl/pdf/2008/no1/optappl_3801p189.pdf