基于Sagnac环形滤波器的多波长掺铥光纤激光器

摘要

为了实现2μm波段多波长激光输出,提出并设计了一种基于Sagnac环形滤波结构的多波长掺铥光纤激光器.激光器由波长793 nm的泵浦源、波分复用器、光纤耦合器、保偏光纤、掺铥光纤以及偏振控制器构成,其中Sagnac环形滤波器以及光纤环形镜作为激光器的反射端.实验中,激光器工作阈值为77.5 mW,通过调节偏振控制器,实现了稳定的单波长激光输出.波长为1852.8 nm的单波长激光输出时,在50 min监测时间内波长最大漂移为0.1 nm,功率最大漂移为0.252 dB,激光3 dB线宽和信噪比分别为0.3 nm和35.7 dB.通过调节偏振控制器,在1850~1900 nm光谱范围内实现了1~4波长的激光输出.%In order to realize the multi-wavelength laser output of 2 μm band, a multi-wavelength Tm-doped fiber laser based on Sagnac loop filter is proposed. The laser consists of a 793 nm pump source, a wavelength division multiplexing, a fiber coupler, a polarization-maintaining fiber, a Tm-doped fiber and a polarization controller, in which the Sagnac loop filter and fiber loop mirror work as reflectors. In the experiments, the laser threshold was 77. 5 mW, and stable single-wavelength laser output was achieved by adjusting the polarization controller. Regarding the 1852. 8 nm laser, in the monitoring period of 50 min, the maximum wavelength drift was 0. 1 nm, the maximum power drift was 0. 252 dB, and the 3 dB linewidth and the signal-noise ratio were 0. 3 nm and 35. 7 dB, respectively. By adjusting the polarization controller, 1—4 wavelengths laser output were realized in the spectrum ranging from 1850 nm to 1900 nm.