Crystal growth and characterization of Ho-doped Lu3Ga5O12 for 2 μm laser

Ho:LuGG single crystal was successfully grown by the Czochralski growth method, and its lattice parameter was found to be 12.2371 Å. Its thermal conductivity was measured to be 5.29 W mK−1 at 300 K. Meanwhile, transmission spectra were recorded at room temperature, and then its absorption spectra were obtained combining with the transmission spectra of LuGG crystal. The transition intensity parameters Ωt (t = 2, 4, 6), the oscillator strengths, fluorescence branching ratios, transition probabilities and the lifetimes of Ho3+ in LuGG crystal were all evaluated by the Judd–Ofelt theory. Furthermore, its emission spectra were also determined and analyzed.

► Bulk single crystal of Ho:LuGG with nomacro-defect was first successfully grown by the Czochralski growth method.
► Its thermal conductivity was found to be 5.29 W mK−1 at 300 K.
► Judd–Ofelt analysis was applied to present potential of Ho:LuGG as a solid state laser material around 2 μm.
► The emission spectra excited at 539 nm was measured, which shows a good tunability at 2 μm nearby.