Growth, structure and spectroscopy of Ho,Pr:LuYSGG mixed crystals for 2.9 m emission

A series of Ho and Pr doped LuYSGG laser crystals were successfully grown by Czochralski method. X-ray rocking curves indicate their high crystalline quality. Crystal structure and basic parameters are provided by XRD and Rietveld refinement. Combining density functional theory, the bandgaps of YSGG and LuYSGG are calculated to be 3.497 and 3.483 eV, respectively. Particularly, the J-O parameters and emission spectra suggest the LuYSGG is more suitable as host for Ho3+ ions and could achieve better 2.9 mu m emission than the YSGG. Meanwhile, the luminescent decay curves show the deactivated Pr3+ ion can greatly narrow the lifetime gap between the I-5(6) and I-5(7) energy levels, which can eventually attenuate effect of self-termination phenomenon on the 2.9 mu m emission.