Growth and spectroscopic properties of Yb3+-doped Li6Y(BO3)3 single crystal

The spectroscopic properties of high-quality Czochralski grown 20% Yb3+-doped Li6Y(BO3)3 single crystal as new promising laser material are presented. The crystal was seeded-grown in the 〈0 1 0〉 direction and its crystallinity was measured using X-ray rocking curve analysis. Low temperature transmission spectrum exhibits broad bands in a short range of wavelengths and two sharp lines at 972.5 and 978 nm, interpreted as two zero-lines of two nonequivalent Yb3+ centers inside the lattice. The fluorescence lifetimes associated to these two intense lines are different: 0.867 and 1.33 ms. An attempt of determination of the Stark sublevels energies of the 4F5/2 and 4F7/2 manifolds of the two Yb3+ nonequivalent ions is given. The polarized absorption and emission spectra were also recorded at room temperature and we conclude that the most favorable emission line for laser application could be around 1042 nm in ng polarization.