Large-size Al3+/Nd3+ co-doped silica glass with 5000 ppm Nd3+ and 50,000 ppm Al3+ doping concentrations was prepared by the modified sol-gel method combined with high-temperature melting and molding technology. Electron probe micro-analyzer tests indicated that high doping homogeneity was achieved with this sample preparation method. The spectral properties of the Nd3+ ions were evaluated. Nd3+-doped silica fiber (NDF) with a core-to-clad ratio of 20/125 μm was drawn from the preform with the Al3+/Nd3+ co-doped silica glass as the core. In the laser oscillation experiment, a maximum output power of 14.6 W at 1.06 μm with a slope efficiency of 39.6% was obtained from the NDF pumped by a commercial 808 nm laser diode. To the best of our knowledge, this is the highest laser power reported for an NDF operated at 1060 nm and prepared by a non-chemical vapor deposition method. In the master oscillator power amplifier experiment, a maximum power of 16.6 W corresponding to a slope efficiency of 30.5% at 1061 nm was also demonstrated. The laser performance of the NDF exhibited the great advantages and potential of the modified sol-gel method in fabricating Nd3+-doped silica glass for a new type of NDFs like large mode area fibers and fibers with large diameter ratio of core/cladding.

稀土的发光和激光性能都是由其4f电子在不同能级之间的跃迁产生的。由于稀土离子的独特性能，使得稀土掺杂光功能玻璃无论作为主动还是被动元器件，均在高功率激光系统发挥着重要作用。掺钕磷酸盐激光玻璃和掺铒磷酸盐激光玻璃，具有高稀土离子掺杂浓度、大尺寸和高均匀制备特性，分别是1 um和1.5 um人眼安全波段重频-大能量激光器的重要增益介质材料；光致热折变玻璃及体光栅器件，可实现波长选择和模式选择功能，具有衍射效率高、热稳定性好和抗损伤阈值高等特点，是高功率激光系统中重要的、多功能元器件。文中主要介绍了上海光机所最近几年在掺钕磷酸盐激光玻璃，掺铒磷酸盐激光玻璃以及掺铈的光致热折变玻璃及体光栅器件的研究进展。