In this article, a precisely controlled, switchable thulium-doped fiber laser (TDFL) with high optical signal-to-noise ratio (OSNR) is proposed and demonstrated. A home-made multimode fiber Bragg grating (MMFBG) with multireflection peaks was used as an optical filter to select the desired lasing channel. Using a manually controlled fusion splicer, the axial misalignment was applied between the single mode fiber and the MMFBG to switch the output wavelength. In the experiment, the number of switchable lasing lines was up to 12, and the fluctuation of the center wavelength and output power was less than 0.03 nm and 0.67 dB, respectively. A maximum slope efficiency of 1.3% was obtained when the axial misalignment was 0 μm, and the OSNR was higher than 65 dB. In addition, the proposed fiber laser was used as an optical fiber laser sensor to quantify the strain applied on the MMFBG, and a sensitivity of 1.16 pm/μϵ was obtained.

中文翻译：

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具有多模光纤布拉格光栅的十二波长可切换掺铥光纤激光器

在本文中，提出并演示了一种具有高光信噪比 (OSNR) 的精确控制、可切换的掺铥光纤激光器 (TDFL)。自制的多模光纤布拉格光栅 (MMFBG) 具有多反射峰用作滤光器来选择所需的激光通道。使用手动控制的熔接器，在单模光纤和 MMFBG 之间应用轴向未对准以切换输出波长。实验中，可切换激光线的数量高达12条，中心波长和输出功率的波动分别小于0.03 nm和0.67 dB。当轴向错位为 0 μm 且 OSNR 高于 65 dB 时，获得了 1.3% 的最大斜率效率。此外，