Efficient Yb3+ sensitized Er3+ emission of Bi2ZnOB2O6:Yb3+/Er3+ single

Bi2ZnOB2O6 single crystals doped with Er3+ and Yb3+ ions were grown by means of the Kyropoulos method. Bi2ZnOB2O6:Yb3+/Er3+ crystals were characterized by high values of nonlinear optical coefficients as well as efficient luminesce of Er3+ ions. The structure, vibrational and luminescent properties of Bi2ZnOB2O6:Yb3+/Er3+ crystals were investigated for the first time. The Raman investigation showed the low phonon energy of Bi2ZnOB2O6 host matrix associated to the vibrations of BO3, BO4, ZnO4 and BiO6 molecular groups, which allow effective phonon assisted energy transfer between Yb3+ and Er3+ ions. The 1532 nm emission of Bi2ZnOB2O6:Yb3+/Er3+ crystals, associated with the I-4(13/2) -> I-4(15/2) transition of Er3+ ions, was excited at 380 (by Bi3+ ions), 488 (by Er3+ ions) and 980 nm (by Yb3+ ions) and efficient Yb3+ sensitization of Er3+ emission was observed. Moreover, the longest decay lifetime equal to 1.36 ms of Er3+ emission at 1532 nm was observed for Bi2ZnOB2O6:Yb3+/Er3+ crystals under 980 nm excitation. Additionally, using the Inokuti - Hirayama model, the kinetics of the fluorescence intensity was analyzed, besides, the energy transfer micro parameter C-DA and the energy transfer rate parameter W-DA were determined for Bi2ZnOB2O6:Yb3+/Er3+ crystals. The results indicate a great potential of new multifunctional Bi2ZnOB2O6:Yb3+/Er3+ crystals for application in the integrated new-generation laser devices. (c) 2021 Elsevier B.V. All rights reserved.