New criteria to choose the best Yb3+-doped laser crystals

Using a model for the quasi three-level laser dealing with Gaussian waves, taking into account the saturation of the pump, the stimulated emission at the pump wavelength, the variation of the pump and laser waists along propa gation ( important for laser diode pumping) and the variation of the laser intensity along propagation, we evaluate the more promising Yb3+-doped crys tals for laser applications: YAG, LNB, GdCOB, YCOB, YAB, C-FAP, S-FAP, CLYP A, KGdW, KYW, Sc2O3, Y2O3, Lu2O3. Our evaluation, established for the CW os cillator regime, differs from that of Deloach and coworkers valid for ns pu lse extraction mode. KYW, KGdW and Sc2O3 are found to be the most efficient when considering the laser extracted power and S-FAP, C-FAP, YAG, KYW and KGdW are the most efficient when considering the small-signal gain of the a mplifier regime.