Jin Xiaoxi, Du Xueyuan, Wang Xiong, Zhou Pu, Zhang Hanwei, Wang Xiaolin, Liu Zejin
College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073, China.
Sci Rep. 2016 Jul 15;6:30052. doi: 10.1038/srep30052.
We demonstrated a high-power ultralong-wavelength Tm-doped silica fiber laser operating at 2153 nm with the output power exceeding 18 W and the slope efficiency of 25.5%. A random distributed feedback fiber laser with the center wavelength of 1173 nm was employed as pump source of Tm-doped fiber laser for the first time. No amplified spontaneous emissions or parasitic oscillations were observed when the maximum output power reached, which indicates that employing 1173 nm random distributed feedback fiber laser as pump laser is a feasible and promising scheme to achieve high-power emission of long-wavelength Tm-doped fiber laser. The output power of this Tm-doped fiber laser could be further improved by optimizing the length of active fiber, reflectivity of FBGs, increasing optical efficiency of pump laser and using better temperature management. We also compared the operation of 2153 nm Tm-doped fiber lasers pumped with 793 nm laser diodes, and the maximum output powers were limited to ~2 W by strong amplified spontaneous emission and parasitic oscillation in the range of 1900-2000 nm.
我们展示了一种高功率超长波长掺铥石英光纤激光器，其工作波长为2153nm，输出功率超过18W，斜率效率为25.5%。首次采用中心波长为1173nm的随机分布反馈光纤激光器作为掺铥光纤激光器的泵浦源。当达到最大输出功率时，未观察到放大的自发辐射或寄生振荡，这表明采用1173nm随机分布反馈光纤激光器作为泵浦激光器是实现长波长掺铥光纤激光器高功率发射的一种可行且有前景的方案。通过优化有源光纤长度、光纤布拉格光栅（FBG）反射率、提高泵浦激光器的光学效率以及采用更好的温度管理，可以进一步提高这种掺铥光纤激光器的输出功率。我们还比较了用793nm激光二极管泵浦的2153nm掺铥光纤激光器的运行情况，在1900 - 2000nm范围内，由于强烈的放大自发辐射和寄生振荡，最大输出功率限制在~2W。
