Doped Gdvo <sub> 4 </ Sub> Laser Crystal Growth And Characterization

Gadolinium vanadate crystal(GdVO4) is a laser host material. As a single crystal ithas large emission cross, wide absorption band, low threshold, high thermoconductivity.For example Nd3+-doped GdVO4 crystal doped by Nd3+ ion has been proved to be a high efficientlaser crystal.In this thesis, liquid phase and solid phase reaction were presented forpolycrystalline raw material synthesis. And the synthetic raw material with these ways were detected by infra-red sepectrpmetry, differential thermal gravimetric analysis, X-ray powder diffraction method, The experimental result showed that the raw material by liquid phase synthesis could meet the demand of crystal growth. Rare earth (Er3+,Tm3+,Yb3+)-doped GdVO4 crystal have been obtained by the Czchralski method. The growth condition, atmosphere and annealing technology were investigated. room temperature ultraviolet absorption, fluorescence emission spectrum, and fluorescent decay curves of various levels have been measured. The spectral strengthparameters (Ωa,Ω4,Ωe) of Er3+,Tm3+ ion were calculated based on the Judd-Ofelt thery. The radiative transition probabilities AJ, J , oscillator strengths PJ,J', radiative lifetime T, the branching ratio BETAJ and emission section ?were also calculated. And florescent lifetimes τ0, microparameters CDA and 70, which describe the interaction between ions and ions were fitted by fluorescent decay curves. τ0 and gamma0 were substituted into the approximate equation for optimal concentration, Er3+ and Tm3+ ions optimal concentrations in GdVO'4 crystal were calculated out and compared with experiment results. The difference of crystals fluorescent intensity was also explained by energy level transition.