Process Theoretical And Experimental Analysis Of Rare-Earth-Doped Laser Glass

Along with the development of optical communication technology and solid-state laser miniaturization there is increasing interest in the field of special fibers doped with some rare-earth element(s). Photonic crystal fiber (PCF), as a new kind of special fiber, possesses many novel optical properties other than the traditional fiber and if is doped with a little mount of rare earth (RE) oxides, can be used to make the ultrahigh power laser.In order to prepare the anticipant PCFs with high quality, which are expected to be used to make PCF lasers, the crucible melting method is suggested to prepare the RE-doped glass first and draw PCFs with it later. My dissertation focuses on the preparations of Er₂O₃, Nd₂O₃, and Yb₂O₃–doped glasses and their aim-related property testing and analysis, such as physical, spectral, optical and lasing properties. The main contents includes as follows:First, the current research situation of the RE-doped laser glass and the RE-doped photonic crystal fiber laser is introduced, and the theory basis of the RE-doped glass laser is deduced in detail.Second, the formula design and preparation process of RE-doped laser glasses are studied. Based on accurate calculation, careful raw materials choosing, the RE-doped laser glass samples with different constituent are prepared by the high-temperature melting process. In order to meet the requirements of the fiber laser, the differential thermal analysis (DTA), the refractive index, the density, the absorption spectrum and the fluorescence spectrum of the samples are tested.At last, four RE-doped glass samples are chosen to be tested. Based on the experiment results of the samples, the absorption cross-sectionσabs, the stimulated emission cross-sectionσ_p, the flurescence lifetimeτ_f, the least particles countβ, the saturation pump intensity Isat and the least pump intensity Imin of the samples are calculated. The stimulated emission cross-sections calculated by the Reciprocity method and by the Fuchbauer-Ladenburger method are compared. The sample with the best laser performance is chosen to be the core of the Yb³⁺-doped photonic crystal fiber.