受激布里渊散射(SBS)是制约窄线宽光纤激光器功率和系统稳定性提升的重要因素,后向传输的斯托克斯(Stokes)光可能会损坏种子和前级放大系统,如何有效抑制SBS或滤除SBS产生的后向Stokes光是高功率窄线宽激光系统必须解决的关键问题。根据光纤激光器的工作波长和SBS频移特性,设计并采用紫外激光加相位掩模板法制备了单模光纤倾斜光纤Bragg光栅(TFBG),搭建系统,开展了SBS信号滤除验证实验。实验结果表明,TFBG对后向SBS信号的平均滤除率大于16 dB,可以很好地保护前级系统,有助于系统稳定工作。

Stimulated Brillouin scattering (SBS) is one of the primary factors that limit the output power and stability of narrow-linewidth high-power fiber laser systems. Backward scattered Stokes light would damage the seed and preamplifier system; therefore, suppressing SBS or filtering the Stokes light is a key problem that needs to be addressed. In this study, we design and prepare a matched tilted fiber Bragg grating (TFBG) using an ultraviolet laser and phase masks in a single mode fiber based on the operating wavelength and the tiny frequency shift of SBS, and perform an SBS signal filtering verification experiment. Experimental results show that the average filtering rate of the TFBG to the backward SBS signal is more than 16 dB, which can well protect the front system and help stabilize the system.