Investigation of Nd:Yb - codoped silica fibers as a laser material

The increasing interest in high power fiber lasers is connected with the task of providing the necessary pump energy at acceptable costs. High power laser experiments with commercially available multi-wavelengths diode laser systems and silica fibers codoped with Neodymium (Nd) and Ytterbium (Yb) demonstrated the potential of this laser concept. Fluorescence investigations of Nd:Yb-codoped silica fibers proved an effective energy transfer from stimulated Nd ions to Yb ions. To get a better understanding of this laser medium we investigated the fluorescence spectra, the fluorescence decay and the laser characteristics both experimentally and theoretically. In conclusion, we present experimental results and a model for the understanding of fluorescence and laser properties of Nd:Yb-codoped silica fibers