Luminescence and Thermal Properties of Er:GSGG and Yb,Er:GSGG Laser Crystals

Er³⁺−doped and Yb³⁺/Er³⁺ co−doped Gd₃Sc₂Ga₃O₁₂ (abbreviated as Er:GSGG and Yb,Er:GSGG, respectively) laser crystals are investigated by using a combination of spectroscopic measurements and thermal characterizations. An absorption peak of Yb,Er:GSGG crystal shifts to 970 nm and its absorption band broadens obviously, which makes the crystal suitable for pumping by a 970 nm laser diode (LD). This crystal also exhibits a shorter lifetime of a lower laser level, a larger emission cross section and higher thermal conductivity than those of Er:GSGG. All these factors suggest that Yb³⁺/Er³⁺ co−doping has a positive effect on improving the spectroscopic and thermal performances in GSGG based laser crystals, and imply that double-doped Yb,Er:GSGG crystal is a potential candidate as an excellent LD pumped 2.79 µm laser material.