We demonstrate the temperature distribution and 2.79 $\mathrm{\mu }$m laser performance in a high-quality Er:YSGG single crystal fiber (SCF) with size of $\Phi$ 0.85$\times$8 mm³ for the first time. Compared with 2$\times 2\times$8 mm³ Er:YSGG bulk crystal, the simulation results show that the center maximum temperature of Er:YSGG SCF is much lower, and the temperature rising and total thermal deformation are evidently reduced, indicating that the SCF possesses more efficient thermal dissipation. Under 970 nm laser diode pumping, a maximum output power of 636 mW with slope efficiency of 20.2% is realized. More importantly, a high beam quality factors $M_x^2/M_y^2$ of 1.28/1.29 is obtained, which is close to the fundamental TEM₀₀ mode, suggesting that the Er:YSGG SCF can act as a promising candidate for mid-infrared laser seed source.

我们演示了温度分布和 2.79 $\mathrm{\mu }$m 激光性能在高质量 Er:YSGG 单晶光纤 (SCF) 中，尺寸为 $\Phi$ 0.85$\times$8 毫米³第一次。与 2 相比$\times 2\times$8 mm ³ Er:YSGG块状晶体，模拟结果表明Er:YSGG SCF的中心最高温度低得多，温升和总热变形明显降低，表明SCF具有更有效的散热。在 970 nm 激光二极管泵浦下，最大输出功率为 636 mW，斜率效率为 20.2%。更重要的是，高光束质量因素${米}_X^2/{米}_{是}^2$获得了 1.28/1.29，接近基本的 TEM ₀₀模式，表明 Er:YSGG SCF 可以作为中红外激光种子源的有希望的候选者。