Experimental study of self-bleaching and radiation equilibrium in output power of fiber lasers at low dose rates
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摘要: 高功率掺镱光纤激光器具有高功率、高效率、可柔性传输的优点,在核设施维护中有着广泛的应用前景。然而,核设施环境中存在的辐照效应会导致光纤激光器功率降低,对实际激光系统应用带来较大挑战。考虑光纤激光器的自漂白效应,探索不同辐照剂量率下光纤激光器暗化与自漂白的关系。结果表明,当辐照剂量率低至一定数值时(比如0.1 rad/s),1 kW光纤激光器在整个实验过程中出光稳定,功率起伏小于1.79%。把观察到的这种现象命名为自漂白-辐照平衡。首次验证了在一定辐照剂量率下,光纤激光器自漂白效应导致的激光功率提升可以平衡辐照效应导致的功率下降,为相关应用中光纤激光器设计提供了有效支撑。Abstract: High-power ytterbium-doped fiber lasers have a wide range of applications in the maintenance of nuclear facilities owing to the advantages of high power, high efficiency, and flexible transmission. However, the irradiation effect in the nuclear facility environment can decrease the power of the fiber laser, which poses a big challenge to applications in such scenarios. Considering the self-bleaching effect of fiber lasers, we explore the relationship between darkening and self-bleaching effect under different irradiation dose rates. When the irradiation dose rate is relatively low, such as 0.1 rad/s, the output power of the 1 kW fiber laser is quite stable with the power fluctuation less than 1.79% during the whole experiment. We name such phenomenon as the self-bleaching and radiation equilibrium (SBRE). It is verified for the first time that under a certain irradiation dose rate, the laser power enhancement caused by the self-bleaching effect of the fiber laser can balance the power decrease caused by the irradiation effect, which provides effective support for the design of fiber lasers in related applications.
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Key words:
- ytterbium-doped fiber laser /
- irradiation effect /
- self-bleaching effect /
- equilibrium
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