Research On The Properties Of Yb Doped Laser Glasses

Ytterbium-doped laser glass is an indispensable medium of high-power laser. With the birth of photonic crystal fiber, people start trying to the combination of Yb³⁺-doped glass medium with photonic crystal fibers because of its superior optical properties, which will be the ideal medium for the preparation of ultra-high-power lasers.Photonic crystal fiber can achieve large mode field area, and maintain single-mode characteristics, which can reduce the nonlinear effect and guarantee the quality of the laser output spot, meanwhile, the cladding air hole of photonic crystal fiber contribute to the elimination of the high-power laser thermal effect. Doped photonic crystal fiber is preparation by the traditional chemical vapor deposition (CVD) method, which is not only the low doping concentration, but the doped area is surrounded by a layer of silica cladding, which can directly impact on the doped photonic crystal fiber size, and reduce lower-doped ion absorption cross section, therefore, Yb³⁺-doped glass was prepared by high-temperature crucible melting method in thesis, Yb³⁺-doped glass can realize the requirement of the Yb³⁺-doped photonic crystal fiber through theoretical and experimental study. The main context includes the following elements:Firstly, A series of Yb³⁺-doped silicate laser glass were prepared by high-temperature crucible melting method, the refractive index, density, differential thermal analysis and other physical performance parameters of silicate glass were tested, and the IR spectra of glass samples, absorption and fluorescence spectra parameters such as spectral properties were tested.Secondly, The physical properties of Yb³⁺-doped silicate glass were studied; the impact of silicate glass composition changes on glass density, refractive index, non-linear physical properties was analyzed.Finally, The absorption cross section, integral absorption cross-section, stimulated emission cross section spectra, such as performance parameters of Yb³⁺-doped silicate glass were calculated by F-L theory and MC theory. The impact of rare earth ions doping concentration and glass composition changes on the glass spectrum were analyzed, the optimum doping concentration was obtained under the conditions of this experiment; the laser performance of the samples was analyzed, the best performance ratio of the laser glass system was obtained.