掺镱光纤光子暗化特性研究

On Photodarkening of Yb-doped Fibers

介绍掺镱光纤光子暗化现象的产生机理、抑制方法和研究方法。搭建了全光纤化高功率激光测试系统。采用CVD工艺制备两种相同镱离子掺杂浓度,不同磷、铝掺杂比例的掺镱光纤,并对其进行斜率效率和光子暗化测试。研究发现,经过优化的抗光子暗化光纤的斜率效率高达72.7%,,在输出功率为734,W的情况下,连续监测24,h,未出现功率衰减,光子暗化效应明显减弱。这种具备优良抗光子暗化性能的掺镱光纤对高功率光纤激光器的制备具有重要意义。

In this paper, the mechanism of photodarkening, all kinds of methods which can mitigate the photodarkening effects in doped fibers, as well as the research methods of photodarkening were introduced. The test system of high-power laser was constructed. The slope efficiency and photodarkening of Yb-doped fibers with the same doping concentration of ytterbium and different doping concentrations of phosphorus and aluminum were tested. The Yb-doped fibers were prepared by CVD technology. It is found that the slope efficiency of the optimized Yb-doped fiber can reach 72.2% and that the output laser power did not decrease within 24 hours, which illustrates the photodarkening effect in the optimized fiber has been weakened obviously. The optimized fiber with weakened photodarkening is important for the manufacture of high-power laser.